Medic is insane but part of that is because assault is underwhelming. But engineer is insane and assault just doesnt perform.
TLDR: RPGs should go from 7 to 3-4 per spawn. Claymores should go from 4 to 2 per spawn. Assault needs a buff with more bandages and/or nades or something else to make fill that role of getting kills. Support needs a wider weapon pool because the m249 is the only usable gun out of the 2 you're allowed to use.
I've played the last 4 playtests and have tried all the classes and engineer feels kind of overwhelming to deal with specifically because of the rpgs. I understand they're supposed to destroy walls and vehicles but I'm not sure if they really need 7 rockets per spawn. It's a lot and the explosives kill through walls as well making them extremely powerful considering there's other wall breaking utility like c4s. I think 3-4 is probably fine for the HEAT rpgs specifically since those are the ones everyone uses. Plus claymores have a similar issue imo where a player doesn't need 4. The map is littered with claymores. I think 2 would be enough sincere there's minimum 32 players per team and at least half of those players have them.
Assault class needs a buff. It's most redeeming quality is that the sledgehammer can break walls with no limit which is nice. Even the wiki only talks about the Assault being for kills but it needs better help doing so. Maybe a passive speed increase on movement would nice or increasing the nade and bandage count up to maybe 7 bandages and 5 nades. In general there needs to be some incentive to use Assault, and because all the other teammates are breaking walls for you and c4 is in the medic class, no need for the sledge.
Support: Being slow isn't great and the restricted gun pool sucks. It just needs to allow the ARs and carbines to help with the movement speed a bit since the armor already slows you down since the only viable gun is the m249 which slows you down beyond belief.