The Battle of Yavin is like 30 ships on maybe 100 because of two main reasons, I'd submit:
1. It was based in large part on historical, real dogfight footage; and
2. Filming and compositing that many things was already a montrously-difficult chore for which ILM practically had to invent equipment to manage.
I happen to think that most of the other battles in the prequel trilogy should have been more like the Battle of Yavin: fewer ships, more real drama. These huge-ass zillion-person space battles are meaningless eye candy. I mean, buzz droids? What crap. Part of what makes the Yavin battle gripping is the fact that it's closer to reality (i.e. real footage of real aerial battles) than the video game-like stuff from the PT. Especially Ep III: you don't see Anakin and Obi-Wan (nor any clones) actually do any real fighting against real adversaries. They fly around, do some fancy-ass rolls, make some droll comments, send several clones to their deaths, and then mosey on up to a heavily-defended starship that happens to have a critical component for the shields mounted on the outside of the ship, and presumably not covered by shields itself. If you want to talk about inconsistencies in plot, etc., why not toss that around for a bit?
Also, it's hard to comprehend now -- more than 30 years later -- just how absolutely brilliant the engineers at ILM in 1975/76 were, to be able to "film" a battle of spaceships and make it look really convincing. In my opinion, now that you can just plop in a thousand other elements with a few mouse clicks and composite the whole thing without half trying doesn't mean you should plop in a thousand other elements.