Wheres the action nowadays? ACM/guns only.
Il2 / DCS / airforce version of world of tanks / ...?
Any others with active ACM subcultures?
They all have their populations. I think AH still has the best populations per arena over all the other games, but thats not saying much. Prime time US is 100-150 depending on the time of year (lower in the summer, higher in the winter) The other games all have smaller limits on arena size.
"Action" is a variable term, it depends on what kind of action you are looking for.