1 - Pet storage: this would be cool, since there are more pets to buy than you can hold. Maybe you could drop pets that you don't want to use off at the storage and withdraw them later. This could effect the pets love in some way, but it would allow the players to try out all of the pets without having to get rid of the pets they own.
2 - Customizable controls: I've mentioned this before and I still stand by this, more so now that we have skills.
3 - Personel Training room: I'm iffy on this. Maybe there could be an in game area which players have to pay x amount of money to enter, and can only enter for an alotted amount of time. They could then choose which monster(s) they want to train with, though the monsters offer no drops and only xp. The stronger the monster, the more they pay. The longer they want to stay, the more they pay, and they are the only player in the room so no kill stealing shenanigans. The spawn rate could be higher as well.
4 - Auto Boot: After a certain amount of inactivity players should be logged off. I have two people on my friends list that have been logged on indefinitely (it's been two-ish weeks) for whatever reason, though they abstain from any and all activity.
Thats it for now, feel free to feedback and whatnot.