Hi Jiji!
I also noticed that the runs here are pretty jumbled organizationally.
There's a lot of short, load-heavy runs that ought to be retimed to game time for fairness' sake, too. For example, Zavada's 2nd place time in lifetime aspiration is actually faster than the (more recent) 1st place by an entire 2 seconds if you take out load times (which is a lot in a category that's performed in less than 30 seconds in real time).
I'd love to help spruce up the place and rearrange the categories! I wouldn't mind handling retimings, either, and have done a bit of the work privately already.
I think it'd be tolerable to have the rest of the skills (about half the skills in the game are missing, really) if they were all sequestered to their own section, just like aspirations ideally should be as well. (There's a category for it but it's empty at the moment.)
I'd really love more challenges that are based on achievements or that reflect ways people play the game as well. I think the existing achievement(ish) categories result in some of the most interesting and diverse routing and exploits (eg mansion baron in half a minute). The ghost woohoo category is fun because it's unique-- you can't just shove ghosts in a woohoo club to skip the relationship.
It forces out different parts of the game out in general. I wasn't even aware of the hermit's existence until your post, for example. (Though with the 10 babies one I think there maybe should be a restriction on how you acquire the babies, otherwise it just turns into adoption menuing simulator.)
I think all of your listed categories could be really fun if you or anyone else would be interested in starting the categories off! I feel like the best way to avoid having tons of empty achievement categories is just to have people submit their runs through the forums, but that might not encourage interest to the same extent.
I also agree that without expansions should be changed to base game + mandatory DLC. At least half the skills in the game are DLC based, and they're sometimes more complex than the BG skills. BG + 1 DLC allows more interesting routing based on stuff that isn't just clubs, tiny house, and incense over and over.
I would love to be a mod so let me know if I can help! I've been doing runs lately and have the spring cleaning bug looking around too ><