In my opinion, it really has very little to do with map size and more to do with the players. If players don't want to fight or are more interested in milking attack runs or bombing AI targets, then smaller maps won't really solve the issue (though they will mitigate it to some extent by forcing fights to occur due to proximity). However, the larger underlying issue will remain, that being that most players really aren't interested in fair fights.
Just last tour, a player in a 190, who I had killed several times previously, heads in my direction while I'm engaged with another player. When their teammate dies, the player immediately turns to base and runs to their ack, despite having slightly more E and alt than me. Knowing it was them, I simply chased them and recorded. This happened several times throughout the night, with the player in question only engaging once they had additional numbers to help them, and avoiding any situation that was a 1v1, 2v2, or anything balanced, regardless of the aircraft I upped (I flew everything from a C205 to a D9).
This same player has been very vocal in this very thread, stating how people should fight and discouraging running. Truth is, the majority of players here do the same thing. Everyone whines about a lack of fights, but few will actually up and fight. It's just the way it is.
This isn't an attack of any sort, simply an observation. I vote for smaller maps, but I don't think that will fix the long-term issue, which is simply player choice.
I think the long-term fix is to simply get more players, which is what HTC is working on.
Just my .02
