Tower Defense Challenge - Part 1 - Basic Concept

Part 1 of the GameDev.net Tower Defense Challenge:

I've always loved playing Tower Defense games and I'm very excited about this challenge. If you're interested in participating you can click the link below for more details.

I'm still in the design phase in terms of the overall graphical look, tower and enemy selection, but I have a good idea on what I would like to do.

I'm thinking about making this game using the mazing feature. For those that are not aware of mazing Tower Defense games, they're typically like so:

You will have an entry and an exit point on your map as seen above. Normally when you don't have any objects blocking the path, the enemies will just take the fastest route from point a to point b.

When you begin mazing you will have something like this:

The main goal is to create a maze that will get the best value out of your towers. There will be a feature that once you start the wave a "test" ghost goes through to confirm if the maze is indeed open, otherwise you'll have to make it possible for the exit point to be reached. I will also prevent building and selling during a phase, but will allow upgrading.

For the first level I'm going to have just one entry point, and for a more extreme version I would like to make more than one entry point and exit point.

I'm still working on the concept of the actual theme, so I'll post back once I have more details on what I'm aiming for.

Some features for this game will include several towers with different abilities, upgrades, and a variety of enemies with different defenses, immunities, and stats (speed, health), ect...

As usual I'll be making the game with C++, but I'm debating on either going 2D or 3D on this. I'm going to look into using Unreal Engine, but I'll have to consider time constraints.

One feature I would really like to add in, is a HERO selection. This HERO can move around on the map and fight the enemies with a variety of abilities such as snaring, slowing, chain lighting, ect... I'll see about doing this!