Yeah I'll be adding difficulty categories soon.

Edit: I ended up creating two different categories consisting of "New Game" and "Any%", mainly due to the use of infinite ammo. The only difficulty settings I created options for were the "New Game" category, again due to the use of infinite ammo. So while there is no "Any% - Hardcore", there is a "New Game - Hardcore"

I agree on a few different points here. The "All Achievements" category is on the longer side, and indeed not immediately attractive to those considering a run for this game (though I still believe it to be important). I also agree we definitely do need more categories.

The only issue with this game is that I see it basically having a nearly infinite amount of categories, so we would need to decide what runners find the most interesting and what a possible future event showcase would want to see (just in case later on down the road a runner would like to submit this to a speedrunning event). I know @sladke mentioned in Discord that once we get more interest from others running, they were going to make a poll to see what category(ies) would be best added. So yeah, we can throw a ton of categories at the wall and just see which one(s) get voted in.

As far as your categories, I definitely think the level based ones and the kill count based ones would be great to see in my opinion. The AFK one does seem a bit tricky, but interesting.

So as far as my opinion goes, get those kill/level categories introduced just to get the ball rolling. For level, I think 100 would be an interesting run. It wouldn't take long at all honestly as I'm sure most of us get 100+ in a single level playthrough. For kills, I also think 1,000 is a good threshold. So both a level 100 and kills 1,000 category would be quick and easy for those wanting to do a shorter run. And plus with the RNG elements of the game, it's going to take a bit before any of these categories can be fully optimized.

All this just being my two cents of course.