can you elaborate on avatars?  disabling uploading does not disable gravatars…  remember, your avatar priority on forum – profile – avatars determines the order in which avatar types are used…

RSS feed is up to you… do you have folks who view the forum via rss?  if everything is done on site or your prefer it that way, they you could disable…

blocking access to wp admin pages wont help with spam… some folks just dont trust WordPress to adequately protect their site if users can access the admin pages… so we provide option for blocking access…

normally, I would recommend not auto deleting users…   some folks wanted a way to auto delete inactive members or ones who have not posted…  lurkers are part of most forums…  I prefer not to auto delete…

recent forum posts widget is available as part of the Template Tags plugin…  it also gives you many other specialty template tags for displaying things… see:  https://simple-press.com/downloads/template-tags-and-widgets-plugin/ and https://simple-press.com/documentation/codex/plugins/our-plugins/the-template-tags-plugin/