What is it? max int? 10?

I believe it is 24

Phil is correct. It's limit to 24 only because there are 24 colors. There has been discussion about making "extended" colors that only come into play on bigger games, but this doesn't exist right now.

The limit for open seats is 10. So, to get a game full of 24 open seats, I would have to add 10, wait for those to fill, then add 10, then wait for those to fill, then add 4 and wait for those to fill? I'll do it, but it kinda sucks since I like larger games.

Is there a reason open seats are limited to 10?
Could the max number of open seats increase to match the max number of players?
Or am I just missing something (most likely scenario)?