I really think other factions should be tested in the beta, for game balance reasons (especially if they want MP to be balanced).
Maybe beta 4?
The devs have confirmed, and alas locked in stone, that we will not be seeing the other races until release. I'm sure some reviewers are going to get to play with them, we aren't.
anyway heres how I see it.
The developers + small group (im guessing they will get some outsiders just to test it a bit) will be the only ones doing any real balance testing (in rts games most balance is issues between races, not mirror matches) and based on previous history of rts games, barely any developers have ever anticipated the most successful strategies and many of them dont appear when the testers are a small amount of people.
examples of games were the developers claimed to do a a lot of balancing testing and it backfired completely, cnc3:
they claimed to have spent more time testing than many other things and the game just became a spam fest of 1-2 units and is still far from balanced atm.
examples of games were the overpowering strategies at release were not anticipated by the developers or most beta testers, starcraft:
Zerg fast expo +mutas was barely used in closed beta (a few testers claimed they found it and didnt reveal it before the game went retail). In the first few weeks (when theres a factor of 10-100 more players things like that are found and maximized to the extreme) it was obvious that this combined with mutas..etc was extremely effective.
I'm not saying that ironclad developers cannot balance, but there is a factor of how many different games are played and by different people with completely different approaches.
