1) what about pets you raise to become mounts? for example; centuars, unicorns, dragons, snakes, fish, turtles, etc... they would still be pets but one of their abilities (like plus to power pips) is transform into mount.
2) what about school mounts or for real fun bucking bronco mounts. My personal fav idea rockin in my head is finding a tempory wander mount or like the secret shop in krok have a teleport that take you to something like the running of the bulls!!! As a reward you get to ride a bull for a mount!!
3) crafting your own designer house. You pick features that you want, possibly have to own a house first and crafting the remodel. For example; adding a dueling circle or a throphy room. I know it is not a full fleshed out idea, but its something to make my house awesome and different.
4) holiday mounts and houses; watch as I ride a reindeer to my own winter workshop, rise my eagle to to my riverboat that has fireworks going off, or riding my rabbit to my underground chocolate castle!!!
these are some thoughts I have been kicking around.
5) I also have ones involving team quests; sign up like PvP to do certain quests. 6) And a hard button that makes bosses more difficult, for example; allowing the Jade oni to summon the other oni like he use to
let me know your thoughts about these am I reaching?