I'm one of the very few Bradley supporters on this board. But even I have to admit that he's been rough to watch at many points this season.
It's certainly a headscratcher why Ainge tossed a 4-year contract at him if he was planning to ship out the last of our talent during this season. Further, I am doubtful about his improvement as a player. He'll never be a good passer/playmaker. His ballhandling will always be subpar and he'll never be a strong finisher at the rim. These things just don't come naturally to him and it shows. He'll always be a good defensive player though, especially if he is allowed to focus on doing so (off the bench, ideally) rather than shooting as much as he currently does.
He does get too much criticism when he plays poorly, and not enough praise when he plays well. But such is the way of a sports forum.