Someone with more recent knowledge correct me on this, but I believe idling is the biggest power drain in Asahi. You will want to shutdown and/or hibernate whenever possible.
ssshhhhh... do not tell anyone I told you...
i would never recommend it to someone who otherwise has a capable computer, of course, but it really isnt that bad. i gave it a pretty thorough test out of curiosity, and when they sponsored a few streamers i watch, it was totally fine. with the caveat that you have a decent internet connection and its probably not good for twitchy games like counter strike.
and, as far as i know, there is limited support for modding and some unsupported workarounds.