Recommended video settings

Hi all, I'm new to video production and am trying to create some art-themed videos to upload to Peertube. Does anyone have recommended video output settings for OBS that would keep the filesize small while still having enough resolution to allow line art to appear readable? Or tips on using something like Handbrake to resize/compress videos without losing quality?

I currently have the following settings in OBS, and my last drawing session resulted a 37min MKV file of 892MB:

• Video encoder = FFmpeg VAAPI H.264
• Audio encoder = libfdk AAC
• Recording format = MKV
• Canvas resolution = 3840x2160
• Output resolution = 3840x2160 (could probably make this 1920x1080)
• FPS = 60 (could probably make this 30)