It is not a bad idea, but it has a lot of things to improve before it can be approved.
First of all: the description.
The description needs an update if it is going to comply with the map submission rules. You can use this template to make it better:
http://www.hiveworkshop.com/threads/map-description-templates.171659/
Some more information would be nice. This must be done in order to get the map approved.
In game, you can only select a few of all the available heroes in the game. It would be nice if you could choose from all melee heroes, plus a few that you have created yourself.
You could also add custom items, to make the gameplay even more interesting.
I would defenitely play this, if only was a little more refined!
Good luck on the updates!