Will be dropping feedback and other stuff here.
Haven't been able to play with people yet, but here's some stuff I wanna get out:
1. A grenade spawn on ow_breach is bugged:
The grenade spawns here:

But will roll down to here each time:

Only to respawn afterwards and do it again, the respawning would be because it's moved from it's spot, getting the respawn noise every so often is kinda annoying as overwatch.
2. One of the combine knocked over one of my turrets, seems it can't be set-up again, one possible fix is to mess with the collision groups so combine can't knock it over, or allow Overwatch to somehow "respawn" it. But I guess the latter is disabled for a reason...
3. It seems there's at least 3 players needed for a proper game, this smells like it could go down the wrong road like Dedacence, which was a great mod, but sitting hours in a server waiting for someone to join just to get a game going is already strange, needing one more is even worse. The straightforward solution would be bots on the resistance team, these will ensure there's always something to play against alone until more people join, I can imagine you have other priorities for now, but eventually a playerbase declines, so it may be worth considering in the long run.
4. There's no quick way to see what weapon your combine troops are using, you need to zoom in and check out their weapon, which seems like a very unconvenient thing to do when actually in action. I'd suggest placing a small weapon icon somewhere near them, I know this is very do-able in Source from my own experiences, so if you need any help with it, I can point you out an easy way to do it. Possibly toggled like the objectives HUD.
5. Does the Team XXX HUD element left over from HL2DM serve any point? It's pretty clear what "team" you're on

6. When Alt Tabbing out as Overwatch the screen will shift very far outside of the map's range over time, usually to the lower right of the screen. Going to the menu and then Alt Tabbing out seems to fix it. Not really an issue worth fixing I guess, but it makes me think of a key to jump the view to an objective, possibly a way to set your own "saved viewpoints"(shift + numberkey?)
7. From the impressions thread by Halsh I gathered players can't join anymore after a short while, Would like to express my support for something like a warmup or anything to give players time to connect properly.
That was all for now, hope to be able to get on with some european people soon!