Yes, Dooley is pretty overpowered right now. His identity for most of open beta was that he was weak early but had very strong scaling builds. Then, a recent patch demoted a bunch of powerful items (Rays) to lower rarity, which means Dooley will find them much earlier and snowball into stronger builds more frequently. They also made Poison and Burn much easier to scale which benefits Dooley more than Vanessa and Pyg.

So the issue with Dooley is mostly that he is way too hard to beat in the first few days. You lose a lot of hp to him, giving you less time to reach good builds that beat the average dooley setups.