Heya, I've been looking at your map for a few days or so. Flows pretty good, item drops seem alright. The merc camp might not see much play with that dragon there but whatever. You went the safe way with the loard.summer mercs, nothing wrong with that, but some other mercs might spice it up and make it more unique (Ashenvale mercs are pretty balanced iirc). A lot of creeps has specific item drops, seems like you're trying to balance blizz's item categories yourself

Btw I don't understand why you put creeps on the bases in a 1v1 map. All in all, balance seems pretty good here with the height variation and such.
I would like to bring another issue with your maps I've noticed for a while - aesthetics. Please don't take it too much to your heart. Your terraining looks way too chaotic here and doesn't really work for me. Imo good terrain should show the player where to go and guide the player plus it should create an atmosphere that might get the players into the story, mood, etc, that the creator planned out. Height variation is another thing with your maps. The one block walls you put at some points of interest are there for the sake of balance but they don't look really good. A good design should go hand in hand with balance while still look good as well. Other than terraining, we have doodads to help us with aesthetics. With doodads you can tell stories within your map and further shape the environment. And you somehow how did tell some stories like those rafts and statues etc. But the way you place the doodads isn't too kind for the eye. Basically it seems like you spam them all round the place. Sometimes less is more and using invisible blockers might look better than using the rock spam. Maybe even trees might do a better job than the debris doodad. I'd like to leave on a good note though so let me say that the eggsack thing looks pretty cool.
Balance comes before the aesthetics though (something I should follow) so yours is a pretty balanced melee map.
I'm pretty curious what your "other" method for symmetry is.