I don't think it matter's too much how large the maps are - people still play seem to play about the same.
Generally, regardless of map size, when I sign in there are always 2 to 3 places where everyone elects to engage enemy forces, and that's where everyone is. It doesn't matter how large or small the map is outside of the 2 to 3 areas, and except for the occasional solitary porker/bomber, the rest of the map is pretty much ignored. With one exception: bigger maps make it easier for those who enjoy them to do sneak NOE's and to conduct a "ground war" while generally avoiding much of a fight.
I'm just happy when I sign in and find the the fighting to be relatively balanced - too much of the time I sign into an arena to find that there only the 2 active areas per side - and one is 80% of one of side's forces against 20% of the other side defending as best they can against overwhelming odds, while across the map you see the remaining 80% of that side's forces whomping on 20% of the third side, with the only thing that changes being which chess pieces are involved at the third corner of the arena.
That's why I like having two arenas available. If you aren't up to being on the short side of a sustained 4 on 1 - but don't enjoy being one of the 4 on the other side of the map where the bulk of your countrymen are, then much of the time the other arena is the only real choice.
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