Why don't we look at the facts and form a basis on those instead?
Here's a recent list of lottery-picked guards. I've included their last season of college ball shooting percentages, both FG and 3PT, and their first back-to-back seasons where they received at least 12 minutes, an NBA quarter, of action per game.
2007 Draft:
Mike Conley - age 22 (college 52%/30% -> NBA first season 43%/33% -> NBA second season 44%/41% -> NBA third season 42%/42%)
2008 Draft:
Derrick Rose - age 21 (college 48%/34% -> NBA first season 48%/22% -> NBA second season 48%/25%
OJ Mayo age - age 22 (college 44%/41% -> NBA first season 44%/38% -> NBA second season 45% 39%
Russell Westbrook - age 21 (college 47%/34% -> NBA first season 40%/27% -> NBA second season 41%/25%
Eric Gordon - age 21 (college 43%/34% -> NBA first season 46%/39% -> NBA second season 47%/37%
DJ Augustin - age 22 (college 44%/39% -> NBA first season 43%/44% -> NBA second season 37%/37%)
OJ Mayo, the best collegiate outside shooter of this group didn't have any trouble adjusting to the NBA, shooting wise. The worst collegiate outside shooter of this group, Conley, went from below average in his first season to top tier in his next. Conley may prove to be the exception to this rule, but the odds are the better shooter you are in college, the better shooter you'll be in the pros. Only Acie Law comes to mind as a recent guard that shot well in college but since fizzled in the pros, and I think that more speaks to the rest of his game.
Bayless, only 21, shot 46%/41% in college. In just 12 minutes per game last season, he shot 37%/26%. Now with 18 minutes per game, he's shooting 41%/27%. As for shooting accuracy, I expect him to progress next year to Conley's second season, Mayo's first season, or DJ's first seasons. It's not likely his stroke would deteriorate to that of Rose or Westbrook, and he has a number of other offensive tools so he shouldn't go the way of an Acie Law.
I think some need to remember that he's just 21 and he's already playing well above a number of his contemporaries, Acie Law, Mike Conley, and DJ Augustin. IMO, and I'm surprised by this, Jerryd has a slightly higher PER than Gordon and Mayo, while also a lower Drtg than Mayo and the same as Gordon.
Obviously Rose and Westbrook are far and away better guards, but, Bayless is stacking up very nicely in the past three drafts amongst other similar players.
As a replacement to last season's Sergio and this season's Steve Blake, he's also proving to be a better option.
There could be better options out there, but they won't be available or the cost will be way too high. Bayless is producing and he's doing so cheaply for the next few seasons. He's young, so the odds are he's going to improve.
Trading him would be a massive mistake IMO.