They added the last 3 heroes btw. D-Va damage looks really low, but then again it might be a range thing, she's using some sort of shotgun type weapon so probably do more at close range. Mei's alt fire is a pain in the dick to use, it has like a 1sec charge time before it fires, definitely good against frozen targets but using it otherwise is annoying. Genji I don't know, looks good but motherfucker is squishy as hell and his reflect shit is really short.
Edit: After a few games, D-Va definitely needs to be upclose to do any damage, but the gameplay is really fun and she's surprisingly not too bad even out of the mech. She feels like the most mobile tank too since the cd on her charge is so low. Genji is definitely squishy, but hot fuck he can be hard to kill if he's just running away, and his damage output is ridiculous especially in ult form.
Mei fucking troll hero. Asshole walled me off with a bunch of enemies like 3times, blocked my hooks like 4times with random ass walls. Shit's way annoying cause unlike barriers you also have to go around and stuff. Her beam is good if you can keep people in it for a bit, but the range is so low, a lot of the DPS will just outright kill you or force you to iceblock before they freeze. Good if people don't see you or whatever though.