"25 players would be too much for a unity game"
??? There are battle royale games made in Unity. Unity is more than capable of handling thousands of dynamic objects just like any other engine.
Among Us uses sprites for everything you see on the map.
The maps would need to be resized and re-balanced to make 25 players work.
Not to mention server stability. If any player is playing on mobile with a poor signal, how do you think that's going to look on both sides?
And let's not forget meetings. How would that even be able to work with 25 players? Sure, discord Voice Channels might be able to make it work. But for textchat, it's going to be a cluster fest.
And 1 imposter games would be too hard for majority of the players. Think about it:
The positives?