Re: Carroll
As much as I would've loved to have re-signed him long-term on a reasonable deal, imo not doing so was the correct move as just 1 additional win that season would have likely prevented us from drafting Exum.
Re: Kanter
While the return was poor (especially when considering the fact that Kanter was a recent #3 overall draft pick), you have to not only consider the circumstances but the results as well. The only argument that can be made is that he should have been traded earlier in the season (ie. when Gobert broke out). The FO basically had zero leverage once Kanter publicly demanded a trade & had to decide between something (a late future 1st & a project), nothing (by allowing him to walk), or a disgruntled player on an undeserved long-term max contract.
If there was a better offer available, I'm sure the FO would have taken it, but considering the fact that the trade not only got something (rather than nothing/a bad contract) from their biggest divisional rival & left them with the bad contract in the process, but also opened up minutes & allowed for a player at the same position with greater potential to flourish, the FO made the best that they possibly could have out of a terrible situation.