On- premise install

we have started a new analytics project in the company and we are preparing our It infra-structure to support Matomo on-premise instances.

Based on our traffic volume (1 site and ± 25M pageviews/Month) we built 2 app servers (16 CPUs, 16+ GB RAM, 100GB SSD disk) and 1 DB server (16 CPUs, 32 GB RAM, 1 TB SSD disk). We set up the app servers as individual instances where one is dedicated to handling all the HTTPS requests and the second one for Report processing. So I need some advices to be sure we will run this project as good as possible:

  1. Are the app servers set up with the best configuration (2 independent instances to handle different roles)?
    Or should they be set up as a cluster?
  2. In case we keep our initial set up, should the 2 instances be always identical? both should have the Matomo version and the same plugins installed also in the same version.
    Or can we keep the first instance as simple as possible and install the plugins (such as Custom Dimension, Funnel, Page Performance report, etc.) just on the report processing server?

Thank you.