I would love to have more space in the inventory and bank space, especially shared bank space, but it maybe a technical issue. While running bosses for loot is fun, leveling a new character helps me stay interested in a game when the grind becomes boring. Playing and leveling a new character is a great way to take a break at the same time keeping the person playing the game. In any loot game, people like to save their favorite items and the current limits for a game with "billions of guns", shields, mods etc is too restricting imo. Im a pack rat though and like to save too much junk at times.
One reason I was hooked to mmorpgs for so long is I could transfer good twink gear over and slaughter encounters that gave me a lot of trouble the first time around. It took mmo's awhile to realize this, but they introduced shared bank space and it was great not always needing to have a trusted friend hand over valuable items like a fungal tunic or worse drop it on the ground in a secure location only to lose the item due to bugs, server problems, theft or any number of reasons. Allowing new characters to get past the early trivial parts of the game didnt break mmo's and doubtful it would break BL2.
I know increasing the shared bank and vault space will be a burden on the db and the engine, which iirc UE3 has a problem with on consoles, maybe Im mistaken though. As it is now, transferring 4 items at a time is ok, but first getting a character to Sanctuary then transferring 4 items at a time is too time consuming when you want to start up a new character.
Maybe there is a way to access claptraps home locker before Sanctuary, but I dont know how. They should make that locker open to new characters from the start. It would make the trip to Sanctuary trivial for a newly created twink, but for people who have lvl 50 characters, it is already trivial. It wouldnt break anything for new players, but it would get rid of some of the headaches for higher lvl characters imo. I know some only see more skill points with a possible lvl increase, but there is many more ways to reward players for gaining new levels past the initial ceiling that wont break the game.
Edit: I must be hallucinating because I could have sworn claptrap had a shared locker in his home place. Im definitely going crazy and have no idea the restrictions on the locker. Just checked on several characters and it is there after you get to Sanctuary, but then disappears after you beat the game. On Normal mode when I beat the game it is gone, but in Sanctuary. With others characters who havent beaten the difficulty, it is there when reaching Sanctuary, so no idea how it works. It should be open from the start for all new characters imo though.
I also dont see a problem in higher level players becoming overpowered and making boss runs much easier as they gain better gear. It only shortens the time farming for loot. Maybe if this was a competitive game with overpowered pvp rewards this could be an issue, but I dont see the issue rewarding people with 100 plus hours played with the best gear. Mudflation could get out of hand with future dlc/expansions, but that isnt that big of a deal in a single player game imo.
Finding the right distance for the carrot is always the toughest part in games based around loot, but players need to get a bite to keep them interested. That was one of biggest complaints about BL1 pearlescent weapons farming(as well as them not being all that great), D3 had the same issues early on, Too Human gameplay glitches aside the best loot was too far out of reach for even some of the most dedicated players with 100s of hours invested.
Loot driven games should have as much attention spent on the gear as any other part, no matter how fun the gameplay and encounters are, if the chance to see any reward for countless hours of work is so small no one notices, players loose interest. Sorry to ramble, but this has always been an issue with loot based games and almost every game gets it wrong.