Recommendations:
1.) First. Get rid of that disgusting blue as your writing in the description. I had trouble reading it.
2.) Work on your grammar. Inside the game and here on your description.
3.) Why not use a better model for the Antenna?
4.) Give the players more time to think about things before the Undead attack such as looking at shops, base layout, etc. Don't let the undead attack until at least 35-60 seconds into the game.
5.) The heroes level up WAAAY to fast. I was level 12 in 3 minutes or so. Already learned all my abilities. The fun part about abilities is the anticipation to learn them 1 at a time, especially an ultimate which can't be learned until level 6 or something. Rework experience gain. Consider adding an ultimate ability.
6.) Speaking of abilities, yours need work. Warcraft 3 is an old game. Everybody knows and hates default Warcraft 3 abilities. Try to be creative and think of better and more interesting abilities which suit the Marine/Zombie/Modern theme of the game.
7.) Could give players a choice of the type of Hero they want. If your aiming for Marine/Military style heroes, you could have, Rocketeer, Medics, Firebats, Snipers, etc.
The game lacks variety and depth. It is very shallow. Some reasons why: The base is small and uninteresting. There is not much in it. There are no Mercenary camps. There are no interesting or useful items (only 6 items which are fairly weak and unoriginal), no builders, only 1 type of hero, there are no side quests, breaks from waves, etc. There list can go on. Basically, you have this hero with boring abilities and that's it. There aren't many tactics or strategies. No interesting game play mechanics. Its very linear and dull. Sorry, I'm being frank. Perhaps you don't want builders in your map, but your map definitely needs something more. Keep at it though. My first maps were much worse than this (and probably still are). So good effort.