With the estimated roster size being 24 and 12 already revealed, that leaves 12 more to be revealed during events. 2 characters are revealed per event. That would mean that they would have to go to 6 more events to reveal everyone.
What probably happened is they ran out of events, or can't attend 6 events, or whatever. So they're closing the gap a little by revealing more with this one event.
No plans that we heard of yet. Gamescom is the only one confirmed. There is still PAX... but who knows if they will even go there? We'll see though, don't worry. :) In any case, 3-4 reveals is awesome, but let's hope they ARE awesome.
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