Smith and Jennings are terrible at what they do, since they aren't playing one-on-one or 2-on-2. They play 5 on 5 basketball which requires being a good teammate - part of which is shot selection. Yes, they have talent, but not enough to build a team around. Drummond's the only guy that fits.
The Pistons are a long way from contending and neither Smith or Jennings should be considered part of the solution anymore than Villanueva or Gordon or Dennis Damn Rodman. Short-term thinking is what landed the Pistons in this mess.