I think the Kyrie trade brought us from an A- to a B-.
is it mostly because of losing the BKN pick?
Mostly. It's rare that you give up the player who had a better season, another starter, and a coveted lottery pick for a guy with similar flaws to the top player you traded away.
Last year, IT was simply better than Kyrie, and it wasn't particularly close. If Kyrie plays at last year's level, we need to fill the production gap of IT, plus Crowder, while also accounting for the future loss of the BRK pick and Zizic.
Irving is just a superior player to Thomas and he's 25. Regular season numbers are nice, but in the playoffs Irving takes his game to another level. Thomas, well, he turns into a low efficient chucker. After seeing what Stevens did for Crawford, Turner, and Thomas, I can't wait to see what he does for the superior Irving.
The only thing that really hurts in that trade is the 2018 pick. However, what certainty do we have that the player would be as good as Irving? Plus, how long will he take to develop? Irving is established and, given his age, provides us with a really long window.
17-18 injured Thomas is not better than Irving. No chance. Plus, you have to worry about the potential risk in losing him to a team willing to "back the brinks truck".
We needed to give up Crowder to give minutes to talented young players, Brown and Tatum. It might offer some initial growing pains, but by the playoffs I expect to see those players vasty improve than their current levels.
Zizic will be likely replaced by a veteran big, so in terms of 17-18 production the latter will be the better player.