I don't consider myself 'Super Rich' but every idea would be welcome, wouldn't it?
1] I'd like a gamble/lottery system, ya know, players donate a amount of zeny to their own liking, and in the end one of the donated players wins all the zeny.
2] More GM/PR activity, before PRs were often to be found in PVP, but since they aren't allowed there anymore you rarely see one. It would be nice if they show up out of nowhere (in prison, cities, or even nifleheim or thor to keep the leeches company.)
3] Cheaper donations/spend credit services. I'm seriously having my hopes on this. When the server switches to eAthena the bills shouldn't be as high as they are now, donations worth of $100 would be enough to keep the server running for a whole month (instead of $2000 per month, or so I heard from a ex-GM. Almost sounds too ridiculous to be true.)
4] As Razer already stated, events. Any event would be nice, invasions/MVP Events, PvP Events, Novice race, whatever more.
5] Again what Razer said, it's no fun seeing the prices being reduced because most useful items are avaible through donation. I'm not saying they should increase their price (wouldn't make sense with my 3rd point), Nu-uh, it'd be more fun to just remove them from the donation rewards entirely.
:]