Here are list of my suggestions they are detailed and with proper, please read and enjoy.

1. Pets System - having pets is the most fun in all RPG games, like spiral Knights. and in this concept, pets should have attacking abilites, instead of other games that pets are just for Display for fame, it's nice to have pets.

2. House System - this is most likely having a room of your own, other games have this. But, I suggest this one in SK, because, it's like having you're own guild, you can customize you're room, sleep in the room while waiting for energy in the next day.

3. Custom Weapons Suggestion - this is like suggesting weapons, and I would go to Bazaar to add a suggestion shop for other players creating Weapons & Armors, .etc So, players can have a fun time.

-P.S. Other more to come