I think your latter trade is more realistic than the first that you started with.
But I still would say that's a lot to give up to get Winslow.
I would rather spend a more modest package to get the #6 or #8 and take Stanley Johnson instead.
I.E., modifying your last proposal:
Piston's get: Sullly (or Olynyk), Young, 33rd
Boston gets: 8th
Boston uses 8th to pick Stanley Johnson and then BPA at 16th, 28th & 45th
I like Winslow, but I feel his value is being over-inflated by his tournament run.
I see Johnson as having just as much upside on both ends of the floor as Winslow and he's already a more versatile scorer. If there is a gap, it's too small, imho, to justify the extra cost to move all the way up into the top 5.
Winslow vs johnson
Winslow won a championship. He was clutch when Duke needed someone to step up (like vs wisc when duke looked dead in the water with okafor in foul trouble). On the other hand Johnson could not do the same for Arizona
Winslow is a better athlete, better leaper (which is big to survive in the nba ). Johnson is not that much stronger from what i saw. Winslow gets the edge on defense.
Johnson is a decent prospect but i worry about his ability to finiah near the basket. His shooting is only ok. We basically have a Johnson in Crowder.
Winslow on the other hand is a more explosive, skilled Crowder.
The fact that "Winslow won a championship" is irrelevant. That's a team accomplishment. You have know way of knowing that if Okafor had declared for AZ instead of Duke, that it might have been Johnson taking the clutch shots in a championship run.
Johnson's lack of an impressive vertical is well known and has hampered his ability to finish now and then. But overall, I feel it is way overblown. He more than makes up for that with his fantastic lateral movement which is explosive in it's own way. That's a big reason he's able to get to the hoop at all and also why he is such a good defender of horizontal space.
The word is that Johnson's unimpressive vertical is due to a flaw in his mechanics that trainers feel confident can be corrected. He's certainly physically strong enough that he should be more explosive vertically so this could be real. Not sure how much stock to put in that until it is realized.
I am very much NOT concerned about SJ's vertical leap. Paul Pierce was not considered all that athletic either. More relevant to me is that he has a wider variety of skills of scoring points, both from outside and inside. He can score both off the ball and with the ball in his hands. The latter is something that Winslow has not been good at.
Crowder is a good player, but he represents Johnson's floor, way under his ceiling.
And again, any perceived gap in the value between Winslow and Johnson comes down to personal preference and in no way in my mind does it justify what it looks like to be the big jump in cost necessary to get Winslow.