Tactics for playing as the Sylvan faction.

and druids can be used for "channeling," which will not only enhance the hero's chaos spells but also some light spells (like resurrection, divine vengeance).

Are you talking about the elder druids? But who takes them? They can't cast spells properly. And even if a druid uses channeling, will the balance of power between the mage and the elf change? Elves can only win as warriors, but they take the highest magic damage of all races (along with orcs). Mages have obsidian gargoyles, which cannot be taken down with fire, cold, or lightning, and they have elemental gargoyles with various negative auras (specifically against unicorns). A mage just needs to cast a crystal of secrets, which they do quite well, and the elven archers are blocked. And if you block the Academy archers, it won't be of much use – gremlins are already weak, and mage-archmages can harm their own units. I'm not arguing that elven archers are the best, but their defense leaves much to be desired. And in general, all elves are weak in defense, except for ents, which cannot be said about mages. And another major drawback of elves is that there are few of them.