Good thread indeed!
Absolute nightmare pick to me is trading up for Mario Hezonja. The kid has all the talent in the world but has done nothing to show it on court so far and has the "I am the world greatest" no-respect mentality I hate. Once he said to an older Croatian teammate "How dare you wear the same sneakers as me". This kid is born a Laker.
Other than him, I really have nobody in this draft I do not want. I'd be disappointed if we trade up and take Oubre, but not a lot.
Last year my nightmare pick was James Young. I don't like no D players and his effort on that end was just hilariously bad. Everybody said how great he played in the final game. I thought he was completely abused on D. Not knowing anything about the Celtics at draft night did not help his cause. Anyway, I hope the kid works hard, grows up and becomes a good player.
I wanted Young, but it was a tough choice between him and Rodney Hood, as I feared that that could come back to haunt us, and just think - we could have gotten him and a 1st rounder this year for AB, thereby correcting a possible error, but nooooo. Ugh. I really wished that he would have traded for another pick or two last year in exchange for Jeff Green so that we could have gotten KJ McDaniels, as well, but once again, nope. Sigh.
Just out of curiosity, who did you want at that spot?
Says who? I hope you're not taking Zach Lowe's post-trade deadline speculation of possible draft day trades as actual offers that were made. The only offers for AB I heard about were late firsts, not late lottery and a good young player
While I realize that, it's been mentioned on here a few times, and besides, what's wrong with getting a late first and Rodney Hood for AB? Apparently, Hood could have been included in such a deal because he had yet to get enough playing time to show his skills, so his value was low at the time (no pun intended, lol
). An injury or two later, however, and he, not surprisingly, blossoms. Doh! 
No, I think your confused.
Lowe reported that Ainge turned down multiple offers for a late first and expirings in exchange for AB at the deadline. I also believe he insinuated the Jazz were one of those teams via a future first they own from GS. He suggested, a long way into the C's playoff run when Hood was getting good minutes, that the Jazz have interest in AB and speculated they would offer their own pick (not very late at 12) in exchange, as DA wouldn't consider trading him for a pick in the 20s (and rightfully so). Considering Ainge's affinity for Bradley, he mentioned Hood as a sweetener in order to get it done.
There's some smoke to that rumor, all the pieces make sense and Lowe is an excellent journalist. But it certainly wasn't like Ainge was presented that deal and turned it down. That never happened. It's just Lowes idea of a trade that both sides would consider and will probably discuss.
The Jazz probably aren't getting anyone at 12 that helps them enough this year to make the playoff push they plan on making. Bradley is a talented player who fits their needs very well, he's only 24 and he's locked into a team friendly contract for the next few years. Who knows, they could probably even snag 33 or 28 from us in a deal like that. For us, we then have 3 first rounders to work with and suddenly trading up to Denver at 7 seems like it's even more possible. If trading Bradley can bet us Hood and Winslow or WCS (or even of we keep the 12 and 16 could get us Johnson and Turner of they keep falling) he would probably make that deal. But trading Bradley for something like #23 and a 8 mil expiring is a rip off for us.
Personally, I don't know if I have a nightmare scenario for the draft. The closest thing would probably be Upshaw at 16, because his red flags are so glaring that giving him a 1st round contract with decent money is a seriously dangerous move. At 28 it's still risky, but not as bad. 33 would be ideal, and I'm not sold on GMs being comfortable giving him a guaranteed contract.
Trading back for marginally better assets while drafting a couple guys like Looney or Alexander would probably disappoint me pretty bad. Ideally, we give up nothing and someone like Johnson or Turner falls to us. But that's unlikely. Most certainly wanna see us move up in some form or fashion to get a good prospect at a position of need.