With the way Dalton is playing, I think going from Ryan to Foles won't kill you. I think Spiller/Jennings have similar value, so this really comes down to Fitz vs. Gronk. I think I would do that. I love Fitz, but unless you're in a 3WR league, I think this trade helps you. If you're in a 3WR league, then I think losing Fitz hurts you too much. After the trade, you can probably flip Kelce for another upgrade which is a nice bonus.