It feels absolutely terrible to know what is happening and not being able to tell anyone.
There's (currently) no pick/ban system, and players are free to change class as much as they want (and Blizzard are actively encouraging changing classes as frequently as the situation requires).Oh wow thats pretty small. Resolves one worry I had though: you only need to know what six classes do at a time, rather than having to distinguish all 21.
Yeah, active memory is a good way of phrasing it - i was more concerned about a system where twelve different silhouettes round the corner and you need to identify all of them at once. It's easier to go "okay, the other team is mei, pharah, junkrat - no not junkrat, roadhog" etc etc.
What I really like is that the icons change to match what skins you have, as well, which makes identifying people with odd skins way easier.And you can always press Tab to see who's there via their icons, which are all super unique. I think that becomes enabled at round start, so you can't insta counter-pick before the game starts.
I keep seeing users on the Overwatch subreddit talking about "when the game has 50/100s heroes" and this idea worries me. While Blizzard hasn't announced any additions of this magnitude, a lot of people seem to expect it (and embrace it) and I have no idea why.