I could envision a scenario where Cleveland uses their 4th pick + a player to Minnesota for the 2nd pick as well. I don't think Williams really fits with Minnesota since they already have Beasley and Love. I don't think Kanter really is needed there either. Oh yeah, and they already have Wes Johnson, who's not bad either.
So I could see a scenario where both Irving and Williams end up in Cleveland and really after that, everything becomes a crap shoot with who goes where.
As for the comments made by BC. I take it with a grain of salt. He's got 2 years for this team to begin showing promise and then if they do, he'll have another year to put that promising team into a competitive stage (see: OKC, Portland etc.). That's enough time. Plus, with Kanter, you're adding a guy who, yes will take time to develop, but if he develops according to 'plan' then you're set and next year take the 3 you need and go from there.