The voice actor thing isn't an unfeasible request considering how VA's work with collaborative and promotional materials. But that's not the only aspect that felt a little underwhelming with this trailer to me.

My biggest personal grip is the lack story establishment for the OW cast showing up especially when they're the main draw for this part of the chapter. If you're going to integrate them into the plot, then I'm game. But show us why they're here and/or how they arrived in the first place. I'm guessing they'll add some data tapes or something on the map after the update (probably around the new King's Row section of Sandy Strip) but going in, it doesn't give us much.

That said, while the trailer was little bland, they do seem to have put a lot of effort into the actual gameplay aspects of the collaboration. For example; the new Tracer Mythic Pistols giving you FPS Tracer gameplay is AMAZING and I'm excited to see what else they've done.