1} Give us a KIT! I most prefer to build em myself, hence why I won't consider several options on today's market.
2} Ease of maintenance. Easy removal of radio tray, easy diff access, etc.
3} Better text in the manuals. I learn better by reading, than studying pictures.
4} X2 CRT style fuel tank...several votes already...I'll add one more
5) Droop - Ryan, if you have the chance, pick up a Duratrax Vendetta TC. I don't know if the way their set up is designed is feasible in 1/8 offroad, but I do think it is ingenious and definitely worth looking into.