I thought the strategy for beating Dark Link was obvious, just crouch and slash wildly. With Shield and Life spells you don't even need to be half as effective as he is.
I ended up using a guide to find my way through the Great Palace, but with a guide it wasn't that bad. Without it it would have taken me a long time to find that hole in the floor under the blocks, although I did get to that spot on my own.
I actually had the most trouble on the second palace. I'm glad the second boss was easy, because the rout to him was complicated and he's deep in the palace.
Overall it was a pretty fun game, I'm glad I played it. I'll probably try the clone, Battle of Olympus.