Heh... it's not that it's going to be bad, as one unit. It's that, if you don't learn to be fairly efficient on polycount from the get-go, it all piles up- 50 triangles here, 40 there.. with 20 units on the screen, that's a 1000 triangles of waste on-screen, and tens of thousands of waste overall, if users are running a shadowmap pass.
It's your first go at all of this, so you should make it as efficient as you can, to learn good habits, instead of learning bad ones and then having to un-learn them... it's easy to model sloppily, but if you then have to fix stuff later, it takes far longer than just doing it right the first time, trust me, I've been there many times
And yeah, uvmapping / skinning's the next big step, and usually the hard one- modeling and animation are relatively easy. I'd get your model really tight before doing that though, a tight model is (usually) easier to uvmap, although that depends on how many face-cutting tricks you use (looks slyly at GMN)...