Discussion about Sylvan (Wood Elves).

In my experience, Academies haven't been dominant in long games. On small maps, yes, and maybe on medium-sized maps, but I don't remember them being effective on large maps.

I think they're good even in long battles; they can accumulate enough knowledge and resources to provide their troops with minor artifacts. They themselves will gather a lot of artifacts. And their army isn't the weakest either.
Of course, it's hard to play against Elves, and a lot depends on luck. Mages go first and can destroy a lot of archers, or maybe the magic will be ineffective. It all depends on the artifacts and the level of play.