Well, let's think about this.
We entered the season with completely unproven commodities at forward. Brown has emerged as a steady, dependable contributor -- so one position is covered. Had Swider returned, presumably he plays the 3, gives us another big guy down on the back line. He was also a very solid rebounder, so he'd actually be a big upgrade over both Benny / Bell, and that would improve what has already emerged as a team strength.
Plus, he's an NBA caliber shooter -- so he'd give us the second [or had he returned, primary] shooting threat, as well as a high double-digit scorer.
I have to think that if he'd returned, this team would be an increment better, which equates to NCAA.