I suggest yet one more filter in stores. You can call it Overflow or something like that. This is meant for old players mostly but it would save a lot of dull work selling useless items. Here is how it works. It checks for items you cannot possibly equip on 3 characters. So more than 3 same shoes, armor, helms, racial skills, 9 warrior weapons, 6 priest weapons, staves, etc. If there is any item over the limit, it would be displayed. You can do it as an item type list selector - maybe name it with "A", so it would stay on top. Like "Above limit" or "All useless". Or you can add one more option for the state button "All/Usable/Unused". This option is a bit dangerous, because one can think he is viewing overflowing items, but he would be in some other view. So you can add some special color to that window or background. You can add a text below the item showing the number of excess compared to usable maximum. For example 13/9. You could show all 13 items here but once 4 are sold and you now have 9/9, items disappear from this window. There are other possible solutions, but anything you decide will be better than scanning for this manually over and over again. This filter should take into account items worn by characters!
Agreed wholeheartly that such feature is desperately needed for experienced players. Looking into future, there is possibility of 4-5 characters at the same time (?). The upper limit should expand a bit like 5 same shoes/traits/etc. I found the "unused" filter not used by me all the time. It should be replaced by this new filter instead.
One more important additional change! There are warrior weapons which even lower the limit! This is connected to yellow tokens cost. You can only use 4 yellow tokens. So it means, that you can only use two same weapons not three on one character. Example: Bejeweled Shortsword costs 2 yellow tokens. So you can use only two instead of three on one warrior. Thus excess/overflow starts not after you get 9 of them, but 6! Solution: Lower filter limit of warrior weapons with two yellow tokens cost to 6 instead of 9.
I'd rather not include treasure as excess. I like to hang on to the epic/legendary stuff sometines. It would be great if we could sell groups of treasure by rarity, but that is probably asking too much. Counting multi-slot items is what drives me batty. In a pinch, I'd have all treasure counted as excess if we could get a "Sell Excess" button.
I don't care about Treasure much myself because it is easy to sell already although it takes a bit of clicking. I would rather see "Sell all" button on the treasure page instead. Such button could also exist on this Excess view. Boring clicking prone to missclicks and mistakes is not a fun thing to do. It is similar to "Take all and leave" from chests after battle.
I have already found out and presented updated idea to my proposal. I think it is much superior, simpler and easier to do for developers. Idea is to get treasure right from the chest when you would get an item which is considered excess. Here is whole suggestion: http://forums.cardhunter.com/threads/suggestion-loot-less-random.4927/