I think that'd be a horrible trade for Minny. They're still in the acquiring legit talent phase. Iggy will not remotely get them over the hump. Grab the best player available and continue your build.
A move like the one mentioned reminds me of the Joe Johnson for Rodney Rogers and Delk move. That gets you nowhere unless your bar is so low that merely making the playoffs is a giant deal.
I don't know, I think you're underrating Iggy. I think there is a very strong chance he is by far the best player in the trade. Williams is a nice prospect, but he is nowhere close to a sure thing, and the chances of him ever becoming even as good as Iggy are not great.
I actually think this is a pretty good trade for both teams. The Wolves give up a marginal asset, and get a guy who fits in well with their team needs. He can run the offense in the half-court as a point forward, and if they bring over Rubio, he would be a great running-mate on the break.
If this were a stronger draft, I would understand the hesitation to give up a pick like that, but in this draft, that is not bad value to get a proven player, who is really just entering into his prime.