The raw map structure seems all right, although you didn't do the details very well.
First of all: the lower expansion mine has a very narrow path (about 1.5 large grid) while the upper expansion mine has several paths.
Red's initial base is slightly larger than blue's initial base.
(The bridge has to go slightly to the right, but that doesn't really matter too much, as you'd need to replace the river as well in that case).
The creeps were quite all right, although you've placed non-neutral units (shadow wolves), which are quite strong and haven't got any drops.
I also prefer not having random creeps (everything pre-set).
Also, would you please not use tables? Not all item drops can be pre-defined in just a few tables, and I'd give the level 9 creep a level 5 perm or 6 charged drop.
Gold coins are (according to me) not really drops, so you'll have to remove those as well ^^
In fact, it's better if you redo all drops (take a look at the blizzard maps as a reference).
The terrain should do (although a few improvements are always welcome! Like adding more tileset variation aorund the place and a few more environmental doodads where due).