If anyone has suggestions for a tournament format bigger than 32 and smaller than 64, lmk. I don't think many people like round-robin finals.
3 person round robin pools can be pretty tolerable if they're used the right way. I'd suggest running it as the first round, and have some sort of tie-breaker in place in case each player wins one game (e.g. 1 point for a win, 2 points for a 2-0 shut-out, total K/D ratio breaks any remaining ties). If you run 16 pools of 3, that gives you 48 players, who then progress into a standard 16 player elimination bracket for the rest of the tournament. In theory, you could also use 8 pools of 5 to give 40 players, but 5 player round robin tends to get a bit annoying. Alternatively, you could do multiple rounds of 3 player pools, giving the possibility for 36 players (12 pools of 3, 4 pools of 3, 4 players remaining for standard elimination bracket) or 54 players (18 pools of 3, 6 pools of 3, 2 pools of 3, 1v1 final)