I like some aspect of focusing the fights and have a recommendation for improvement.
---- First, my reasons why I like focusing the fights. ----
Focusing the fights clearly makes it much easier to find well-attended fights, which I like.
Focusing the fights countracts the apparent human tendency to reinfoce lopsided fights. The way things were, it was often the case that many players would choose to be the 21st player in a 20-on-5 fight in preference to joining, say, a 10-on-10 fight; and most people eventually leave a 5-on-20 fight when they are on the side of 5. This is a feedback mechanism that works against balance. Focusing the fights tends to combine the fights together, which helps correct imbalances.
I enjoy well-attended, relatively balanced fights much more than lopsided ones or sparsely attended ones. For 1-on-1's, I can go to the dueling arena or hang out at the periphery of a bigger fight -- so I don't necessarily lose that aspect if fights are focused.
---- Second, my suggestion for improvement. ----
I do think that restricting the fight to be over only a couple spots on the map is more restriction than is optimal. While I do enjoy the air action, there is less variety in choice, and there are times when there will not be any CV's or ground vehicles that can be involved (when it's far inland or when there are no vehicle spawns from one base to the next capturable base).
Focusing the fights is not altogether artificial, though. In real WWII, commanders had to keep in mind supply lines. In fact, the issue of supply lines is another reason I like some restriction rather than a wide-open capture map.
What I suggest is to have more supply lines and to use those to determine which bases can next be taken -- like was involved in the Stalin's Fourth scenario. There, you typically took the next base on a supply route, but there were several supply lines. It looked like this:

That's what I'd like to see. It focuses the fights more than the old way, but it is less restrictive than the current test way. It will focus the fights, but allow GV's and CV's almost always to have something to do, and it gives a little more choice. You'd have maybe 4 bases (per enemy) to choose to take next instead of just 1.