Trading Crowder makes so little sense from a luxury tax perspective. Are we keeping all 3 of Smart, IT and AB? We'd be looking at a LT bill pushing $100m. Wyc is rich but he isn't a Russian oligarch.
I don't see why we can't have 4 SF's. SF isn't really a position in Stevens's sytem; you saw Brown play plenty of "2" last year, Crowder play plenty of "4", you saw Smart playing the 3, Green playing either 2 or 3, etc.
This roster is perfectly balanced if you want to play with 1 PG, 3 wings and 1 big most of the time:
PG: IT, Smart
Wing: Hayward, Crowder, Brown, Tatum, (Smart)
Big: Horford, Zizic