Heimerdinger: Unit of the future!
I don't know what his ult should be but there are a ton of fun options + everyone loves the donger. The main point is to have Heimer be a lvl 5 Hextech Yordle though ya dig?
Maybe a wild/phantom could be cool. Hecarim might fit that.
A level 3 or 5 void critter might be nice?
Another robot/exile or a new stand-alone type of unit buff.
Another lvl 1 or a lvl 2 knight so that early 4 knight is possible to insure more overtimes early on because that is what we all really want to see most.
/
? Shockwaves and windslashes would be really cool.