BANK-
Everyone likes to collect things, and when they have too much it needs to be stored. A bank or a deposit area in-game would be nice. One of my goals in the game is to own every weapon, armor, shield, and have them level 10. A bank would come in handy for storing stuff that ive mastered. Not only that, a bank could be useful for storing equipment, so that way, theres only a couple of each type of equips, perfect for switching out in break stations.
BEASTBOOK-
A simple book that keeps all the information of the beasts you have faced on your journey. It would say what type of creature it is. It would list it's weaknesses, its strentgh, what it's resistant to. It would also keep information about the drops you have received from that creature and that'd be pretty useful for everyone so they can figure out what elevator to take for all their crafting needs.
LOGBOOK-
A book on all the places you have been to. It would list how many times you have cleared, what monsters you have faced in that dungeon. Just basic stats that's cool to look at. Anyways i've been to devilish drudgery : wired for synergy to many times, so i thought it would be neat to check out how many times iv'e actually been there.
this is one of the rare games where your inventory is unlimited...
you can keep everything on you for trading conveniences
the only good bank for Spiral knights is an unlimited storage bank to store all your not needed stuff
But its not that impt.. a way to rearrange the items in our arsenal would be nice
the 2 books are like achievements =p
nice.