Curious if you really believe that Witten and a 2nd was fair value ?
My thoughts: Witten is likely to last longer than Manning, and I don't know what I have with Thomas sans Manning. And the 1.5 PPR hurts Thomas' value in relation to Witten's. Thomas caught 12 TDs last season--I wouldn't bet on that to hold. If that drops down to 8, which is still a lot, how do his numbers stack up to Witten's?
I think Thomas has more value, but a lot of that is market value. In a 1.5 PPR league, I'd value them pretty close to evenly, myself, and wouldn't even add a 2nd to Witten. I'm of the opinion that Witten can play to 36-37, however.