I'm not sure trading Jennings is in the team's best interest. Jennings, for his flaws an potential overlap with Reggie, is still the second best playmaker on the team. The team already struggles to score in general, and the bench has been terrible for most of the year. Jennings sticking as the 6th man gives the bench some life, and at least a chance to generate good looks when Drummond and Reggie sit. Losing Jennings means more Steve Blake, who should already be retired and looks like he's running in lead shoes.
Further, a Jennings trade can't solve the main problem the team faces: not enough Drummond. With Drummond on the floor, the Pistons are a good team that can hang with even better teams. When Drummond hits the bench, the Pistons turn into the Sixers. The development of the team as a whole will come down to growth potential. That is, finding pieces that fit early, but can develop into more well-rounded pieces. Stanley Johnson is that kind of piece, KCP might be. These are normally guys that you draft, rather than just pick up in FA or trades. If another team is willing to part with a young player on his rookie contract or a late first, then sure, move Jennings. But I just don't see it.
Side note: How long do we need to wait to question the wisdom of Reggie's contract. He's been good, but he plays almost ALL of his minutes with Drummond, whose mere presence gives him more room to work. The team has been fine in lineups without Reggie as long as Drummond is on the floor, but the opposite isn't even close. He still hasn't reached league average efficiency as a scorer, his passing has returned to normal (some may call this regression, but the sample size was never large enough to presume he had actually improved), and he's still minus defender. There is something to be said for the volume of shots he creates and takes, but most of that is old-school thinking. Wouldn't a healthy Jennings, or a lot of other average starting PGs be just as good with the same freedom and teammate (Drummond)?