Collusion might be doable by mouse-clickiing on a player's name to request collusion, and then have that accepted with a mouseclick to the requester's name.
This should be the way it's done for the "close to the original" version.
Of course, this would add to game length, which some express some discomfort at (but that's not relevant to our discussion at this point).
It might add to the game length, but that's how it was in the original version. IMHO that's only a valid argument for the planned "improved" version.