Hand-drawn art for a game

I’m currently making my first game (a defence game) and I was wondering if it would be a good idea to hand-draw the enemies? They’re going to be organic ships (sort of like the Wraith from Stargate Atlantis or the Tyranids from W40K) and I think I could do a better job making them by hand then with a computer. I’ll be drawing them on an A3 sheet in pencil, outlining in black permanent marker, then scanning them to a computer where I will do some touch-ups and animate them.
I’ll post them once I’ve finished. I’ve done 4 pencilled versions so far, but none are ready for scanning.

Do you think this would be a good idea or does anyone else have a better one?

This would be a good idea indeed… though it may take some time to do.

Here’s the original concept designs. At least the finalised ones. The A3 sized ones are nowhere near ready.