How to add new PollerOption to workflow?

Thanks Tihomir, we are currently using Temporal Java SDK 1.16.0 . A few related questions.
Q1. To reduce the number of pollers/workers polling on this namespace - can I use the setMaxWorkflowThreadCount() API ? - This is currently set to the default value of 600 - does this still need to be reduced ?

 /** Java SDK **/
 private static final int DEFAULT_HOST_LOCAL_WORKFLOW_POLL_THREAD_COUNT = 5;
 private static final int DEFAULT_WORKFLOW_CACHE_SIZE = 600;
 private static final int DEFAULT_MAX_WORKFLOW_THREAD_COUNT = 600;

Q2. frontend.namespaceCount - What is this counter used for ? is there a way to calculate the appropriate lower-bound for this w.r.t number of active workflows ? Also, is there a way to update this value using the Temporal SDK ?

Q3. We currently have a single pod running Temporal frontend. Should the number of pods for Temporal frontend be based on the mean CPU utilization of the frontend pod ?