Thanks for starting this, lots of useful stuff here. One thing that worked for me outside itch, in case it helps:
I made short vertical videos for my game. The ones that opened on a real moment (a text from the character's mom, an unknown number at 3am) kept 2 to 3 times more viewers than the ones that pitched the game ("5 ways to get rich in this game"). So I'd say: show one moment, not the feature list.
Also, the first one or two videos of a day did much better than the third and fourth, so posting less often worked better for me.
I'm new on itch (released yesterday), so I can't say much about followers here yet. What has worked best for you so far?