Is there a list of missable events (either here, or on the wiki) and what to do to avoid them?
There are many missable events, sure, but you can easily prevent that by not raising you affection and concentrate on lust until its 30. Just in case. Its the ones that you can miss and dont even know about it until much later.
The other missables are all on yourself. I mean, Tell Karin that you dont fk around with Kirin, fk Ami, fk every side character.
Dont do Chikas Shredinger or something event (15 love points, dorm event) until the beach event or you will be a bad homie and miss some of the events.
And there is a missable happy scene, worry about it when you will be in front of the PC and enter your IP and password when prompted. There is a correct and "another one" that lead to that scene. And another scene behind some options in another reset.
Yeah, thats pretty much it, currently. Maybe missed something, but not really sure.
The list is a bit huge, but if you do what I stated above - I doubt you miss anything.