Having to choose either 2 player or 4 player is an odd one. Why not both?
Import 2 Player versions of games that have multiple options? yes/no
Import 4 Player versions of games that have multiple options? yes/no
I know I'm in the minority, but I also know at least a couple other folks out there have setups that can be both 2 and 4 player setups. I have 2x two player cabinets, that can be linked together to create a four player cabinet with mirrored screens (all hardware). So sometimes I want the two player version, sometimes I want the 4 player version.
Although this only matters for a few titles that have characters hard locked to play number. If you can choose you character regardless of what player slot you are, its 4 player version always.