(I know scoreboard features are on the way, and that's super exciting!) One thing I've always wanted is a way to detect player inputs via command blocks / redstone. For example, there could be a scoreboard objective which increments when the "jump" key is pressed. An alternate form of this could also be useful, where the value is "1" when the key is held and "0" when the key is released. Up until now I've used re-textured carrots on sticks to detect right clicks which can be a cumbersome workaround.