I think we just take Joey as an upgrade to Polley and leave it at that.
I mean Joey is basically that shooter off the bench with better (or at least more willing) passing and rebounding. Also more steals. Sure he gives up height but Polley never played big.
Just for comparison:
Polley had a total of 56 assists in five years at UConn, or 11 assists a year on average. Joey has 10 assists so far in five games. To be fair Joey turns it over a ton more also. Both things to monitor as he should have less of a distributor role with Jackson/Newton being primary ball-handlers and Diarra/Alleyne secondary in most lineups.
Polley also only had 256 rebounds in five years, or about 51 rebounds a year. Joey has 19 in five games. Polley had 40 total steals in five years, or 8 a year. Joey has 6 so far.
Polley did block an odd shot and I don't expect that from Joey.
Long term, if it's not a blowout, I expect him to get 12-18 a game filling in as the fifth or sixth perimeter player behind Jackson, Newton, Hawkins, Alleyne and fighting for minutes with Diarra. In really tight games I expect those minutes will drop even further, especially if Johnson comes back and can backup Karaban.
Right now Jackson is needed to backup the four but that means more minutes for Diarra and Joey C backing up 1-3.
The four is probably the weakest spot right now. Karaban has been fantastic but he is still a freshman and Jackson is his best backup right now which isn't ideal. Johnson would sure shore up that possible weakness with his length and athleticism.