diff --git a/README.md b/README.md
index 769a7df..022c9ab 100644
--- a/README.md
+++ b/README.md
@@ -103,7 +103,12 @@ partition configuration for each.
 
 `openhpc_cluster_name`: name of the cluster.
 
-`openhpc_config`: Optional. Mapping of additional parameters and values for `slurm.conf`. Note these will override any included in `templates/slurm.conf.j2`.
+`openhpc_config`: Optional. Mapping of additional parameters and values for
+[slurm.conf](https://slurm.schedmd.com/slurm.conf.html). Keys are slurm.conf
+parameter names and values are lists or strings as appropriate. This can be
+used to supplement or override the template defaults. Templated parameters can
+also be removed by setting the value to the literal string`'omit'` - note
+that this is *not the same* as the Ansible `omit` [special variable](https://docs.ansible.com/ansible/latest/reference_appendices/special_variables.html#term-omit).
 
 `openhpc_ram_multiplier`: Optional, default `0.95`. Multiplier used in the calculation: `total_memory * openhpc_ram_multiplier` when setting `RealMemory` for the partition in slurm.conf. Can be overriden on a per partition basis using `openhpc_slurm_partitions.ram_multiplier`. Has no effect if `openhpc_slurm_partitions.ram_mb` is set.
 
diff --git a/defaults/main.yml b/defaults/main.yml
index ea91c75..94ba868 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -12,7 +12,36 @@ openhpc_packages:
 openhpc_resume_timeout: 300
 openhpc_retry_delay: 10
 openhpc_job_maxtime: '60-0' # quote this to avoid ansible converting some formats to seconds, which is interpreted as minutes by Slurm
-openhpc_config: "{{ openhpc_extra_config | default({}) }}"
+openhpc_default_config:
+  # This only defines values which are not Slurm defaults
+  SlurmctldHost: "{{ openhpc_slurm_control_host }}{% if openhpc_slurm_control_host_address is defined %}({{ openhpc_slurm_control_host_address }}){% endif %}"
+  ProctrackType: proctrack/linuxproc # TODO: really want cgroup but needs cgroup.conf and workaround for CI
+  SlurmdSpoolDir: /var/spool/slurm # NB: not OpenHPC default!
+  SlurmUser: slurm
+  StateSaveLocation: "{{ openhpc_state_save_location }}"
+  SlurmctldTimeout: 300
+  SchedulerType: sched/backfill
+  SelectType: select/cons_tres
+  SelectTypeParameters: CR_Core
+  PriorityWeightPartition: 1000
+  PreemptType: preempt/partition_prio
+  PreemptMode: SUSPEND,GANG
+  AccountingStoragePass: "{{ openhpc_slurm_accounting_storage_pass | default('omit') }}"
+  AccountingStorageHost: "{{ openhpc_slurm_accounting_storage_host }}"
+  AccountingStoragePort: "{{ openhpc_slurm_accounting_storage_port }}"
+  AccountingStorageType: "{{ openhpc_slurm_accounting_storage_type }}"
+  AccountingStorageUser: "{{ openhpc_slurm_accounting_storage_user }}"
+  JobCompLoc: "{{ openhpc_slurm_job_comp_loc }}"
+  JobCompType: "{{ openhpc_slurm_job_comp_type }}"
+  JobAcctGatherFrequency: "{{ openhpc_slurm_job_acct_gather_frequency }}"
+  JobAcctGatherType: "{{ openhpc_slurm_job_acct_gather_type }}"
+  SlurmctldSyslogDebug: info
+  SlurmdSyslogDebug: info
+  PropagateResourceLimitsExcept: MEMLOCK
+  Epilog: /etc/slurm/slurm.epilog.clean
+  ReturnToService: 2
+
+openhpc_config: {}
 openhpc_gres_template: gres.conf.j2
 openhpc_slurm_configless: "{{ 'enable_configless' in openhpc_config.get('SlurmctldParameters', []) }}"
 
diff --git a/filter_plugins/slurm_conf.py b/filter_plugins/slurm_conf.py
index 3f0ba56..9c38638 100644
--- a/filter_plugins/slurm_conf.py
+++ b/filter_plugins/slurm_conf.py
@@ -22,16 +22,6 @@
 # Pattern to match a hostname with numerical ending
 pattern = re.compile("^(.*\D(?=\d))(\d+)$")
 
-def _get_hostvar(context, var_name, inventory_hostname=None):
-    if inventory_hostname is None:
-        namespace = context
-    else:
-        if inventory_hostname not in context['hostvars']:
-            raise errors.AnsibleFilterError(
-                "Inventory hostname '%s' not in hostvars" % inventory_hostname)
-        namespace = context["hostvars"][inventory_hostname]
-    return namespace.get(var_name)
-
 def hostlist_expression(hosts):
     """ Group hostnames using Slurm's hostlist expression format.
 
diff --git a/tasks/runtime.yml b/tasks/runtime.yml
index a19aa89..b08a451 100644
--- a/tasks/runtime.yml
+++ b/tasks/runtime.yml
@@ -70,43 +70,9 @@
   notify: Restart slurmdbd service
   when: openhpc_enable.database | default(false) | bool
 
-- name: Make local tempfile for slurm.conf templating # ensures simultaneous runs don't clobber each other
-  ansible.builtin.tempfile:
-  register: _slurm_conf_tmpfile
-  delegate_to: localhost
-  when: openhpc_enable.control | default(false) or not openhpc_slurm_configless | bool
-  changed_when: false # so molecule doesn't fail
-  become: no
-
-- name: Template basic slurm.conf
+- name: Template slurm.conf
   template:
     src: slurm.conf.j2
-    dest: "{{ _slurm_conf_tmpfile.path }}"
-    lstrip_blocks: true
-    mode: 0644
-  delegate_to: localhost
-  when: openhpc_enable.control | default(false) or not openhpc_slurm_configless | bool
-  changed_when: false # so molecule doesn't fail
-  become: no
-
-- name: Customise slurm.conf
-  community.general.ini_file:
-    path: "{{ _slurm_conf_tmpfile.path }}"
-    option: "{{ item.key }}"
-    section: ''
-    value: "{{ (item.value | join(',')) if (item.value is sequence and item.value is not string) else item.value }}"
-    no_extra_spaces: true
-    create: no
-    mode: 0644
-  loop: "{{ openhpc_config | dict2items }}"
-  delegate_to: localhost
-  when: openhpc_enable.control | default(false) or not openhpc_slurm_configless | bool
-  changed_when: false # so molecule doesn't fail
-  become: no
-
-- name: Create slurm.conf
-  copy:
-    src: "{{ _slurm_conf_tmpfile.path }}"
     dest: /etc/slurm/slurm.conf
     owner: root
     group: root
diff --git a/templates/slurm.conf.j2 b/templates/slurm.conf.j2
index 3d29994..3ffeff5 100644
--- a/templates/slurm.conf.j2
+++ b/templates/slurm.conf.j2
@@ -1,140 +1,18 @@
-#
-# Example slurm.conf file. Please run configurator.html
-# (in doc/html) to build a configuration file customized
-# for your environment.
-#
-#
-# slurm.conf file generated by configurator.html.
-#
-# See the slurm.conf man page for more information.
-#
 ClusterName={{ openhpc_cluster_name }}
-SlurmctldHost={{ openhpc_slurm_control_host }}{% if openhpc_slurm_control_host_address is defined %}({{ openhpc_slurm_control_host_address }}){% endif %}
 
-#DisableRootJobs=NO
-#EnforcePartLimits=NO
-#EpilogSlurmctld=
-#FirstJobId=1
-#MaxJobId=67043328
-#GresTypes=
-#GroupUpdateForce=0
-#GroupUpdateTime=600
-#JobFileAppend=0
-#JobRequeue=1
-#JobSubmitPlugins=lua
-#KillOnBadExit=0
-#LaunchType=launch/slurm
-#Licenses=foo*4,bar
-#MailProg=/bin/mail
-#MaxJobCount=10000
-#MaxStepCount=40000
-#MaxTasksPerNode=512
-MpiDefault=none
-#MpiParams=ports=#-#
-#PluginDir=
-#PlugStackConfig=
-#PrivateData=jobs
-ProctrackType=proctrack/linuxproc # TODO: really want cgroup but needs cgroup.conf and workaround for CI
-#Prolog=
-#PrologFlags=
-#PrologSlurmctld=
-#PropagatePrioProcess=0
-#PropagateResourceLimits=
-#PropagateResourceLimitsExcept=
-#RebootProgram=
-SlurmctldPidFile=/var/run/slurmctld.pid
-SlurmctldPort=6817
-SlurmdPidFile=/var/run/slurmd.pid
-SlurmdPort=6818
-SlurmdSpoolDir=/var/spool/slurm # NB: not OpenHPC default!
-SlurmUser=slurm
-#SlurmdUser=root
-#SrunEpilog=
-#SrunProlog=
-StateSaveLocation={{ openhpc_state_save_location }}
-SwitchType=switch/none
-#TaskEpilog=
-#TaskPlugin=task/affinity
-#TaskProlog=
-#TopologyPlugin=topology/tree
-#TmpFS=/tmp
-#TrackWCKey=no
-#TreeWidth=
-#UnkillableStepProgram=
-#UsePAM=0
-#
-#
-# TIMERS
-#BatchStartTimeout=10
-#CompleteWait=0
-#EpilogMsgTime=2000
-#GetEnvTimeout=2
-#HealthCheckInterval=0
-#HealthCheckProgram=
-InactiveLimit=0
-KillWait=30
-#MessageTimeout=10
-#ResvOverRun=0
-MinJobAge=300
-#OverTimeLimit=0
-SlurmctldTimeout=300
-SlurmdTimeout=300
-#UnkillableStepTimeout=60
-#VSizeFactor=0
-Waittime=0
-#
-#
-# SCHEDULING
-#DefMemPerCPU=0
-#MaxMemPerCPU=0
-#SchedulerTimeSlice=30
-SchedulerType=sched/backfill
-SelectType=select/cons_tres
-SelectTypeParameters=CR_Core
-#
-#
-# JOB PRIORITY
-#PriorityFlags=
-PriorityType=priority/multifactor
-#PriorityDecayHalfLife=
-#PriorityCalcPeriod=
-#PriorityFavorSmall=
-#PriorityMaxAge=
-#PriorityUsageResetPeriod=
-#PriorityWeightAge=
-#PriorityWeightFairshare=
-#PriorityWeightJobSize=
-PriorityWeightPartition=1000
-#PriorityWeightQOS=
-PreemptType=preempt/partition_prio
-PreemptMode=SUSPEND,GANG
-#
-# LOGGING AND ACCOUNTING
-#AccountingStorageEnforce=0
-AccountingStorageHost={{ openhpc_slurm_accounting_storage_host }}
-{% if openhpc_slurm_accounting_storage_pass | default(false, true) %}
-AccountingStoragePass={{ openhpc_slurm_accounting_storage_pass }}
-{% endif %}
-AccountingStoragePort={{ openhpc_slurm_accounting_storage_port }}
-AccountingStorageType={{ openhpc_slurm_accounting_storage_type }}
-AccountingStorageUser={{ openhpc_slurm_accounting_storage_user }}
-#AccountingStoreFlags=
-#JobCompHost=
-JobCompLoc={{ openhpc_slurm_job_comp_loc }}
-#JobCompPass=
-#JobCompPort=
-JobCompType={{ openhpc_slurm_job_comp_type }}
-#JobCompUser=
-#JobContainerType=job_container/none
-JobAcctGatherFrequency={{ openhpc_slurm_job_acct_gather_frequency }}
-JobAcctGatherType={{ openhpc_slurm_job_acct_gather_type }}
+# PARAMETERS
+{% for k, v in openhpc_default_config | combine(openhpc_config) | items %}
+{%  if v != "omit" %}{# allow removing items using setting key: null #}
+{%    if k != 'SlurmctldParameters' %}{# handled separately due to openhpc_slurm_configless #}
+{{ k }}={{ v | join(',') if (v is sequence and v is not string) else v }}
+{%    endif %}
+{%  endif %}
+{% endfor %}
 
-# By default, SLURM will log to syslog, which is what we want
-SlurmctldSyslogDebug=info
-SlurmdSyslogDebug=info
-#SlurmSchedLogFile=
-#SlurmSchedLogLevel=
-#DebugFlags=
+{% set slurmctldparameters = ((openhpc_config.get('SlurmctldParameters', []) + (['enable_configless'] if openhpc_slurm_configless | bool else [])) | unique) %}
+{% if slurmctldparameters | length > 0 %}
+SlurmctldParameters={{ slurmctldparameters | join(',') }}
+{% endif %}
 
 # LOGIN-ONLY NODES
 # Define slurmd nodes not in partitions for login-only nodes in "configless" mode:
@@ -142,8 +20,6 @@ SlurmdSyslogDebug=info
 NodeName={{ node }}
 {% endfor %}{% endif %}
 
-PropagateResourceLimitsExcept=MEMLOCK
-Epilog=/etc/slurm/slurm.epilog.clean
 
 # COMPUTE NODES
 {% for nodegroup in openhpc_nodegroups %}
@@ -183,8 +59,3 @@ PartitionName={{partition.name}} {{ '' -}}
     Nodes={{ partition.get('nodegroups', [partition.name]) | map('regex_replace', '^', 'nodegroup_') | join(',') }} {{ '' -}}
     {{ partition.partition_params | default({}) | dict2parameters }}
 {% endfor %}{# openhpc_partitions #}
-
-{% if openhpc_slurm_configless | bool %}SlurmctldParameters=enable_configless{% endif %}
-
-
-ReturnToService=2