Correct me if this isn't how this works but...could I be an admin? I know I only post stories from other sites but barley anybody besides me, you and Psychopasta post anything to this site anymore and I got some ideas on new categories and for getting rid of superfluous categories.
Hit me up... and I'll work on that.
Also, the categories thing, you could pretty much add them as much as you like - as long as they aren't stupid. By stupid I mean "Killer" or something ridiculous of the sorts.
Make sure you keep on using a certain category you came up with consistantely and it's all good.
Same goes for removal, if it's not crazy and consistant, sure.