In terms of adding the Operation Breakout maps, I only support adding Castle and Blackgold. For the most part, I think that Castle and Blackgold should be able to support 32 players fairly well, although I don't have a good idea of how sided they are yet.
Mist might end up being good fun for 5 vs 5 once more people have learned how to play it, but the other maps are garbage, imo. Overgrown initially seems like a well put together map, but if you start to look at the fine details it should become quite clear to you that the map is broken. Rush is just dull, and Insertion isn't even a proper CS map. I love changing things up, but fuck Insertion...JUST.NO.