I've not looked into this sort of thing much, but one piece of advice I'd give you from when I used to play tabletop wargames (really quite a lot) is to make sure you leave your system flexible enough to adjust in response to playtesting.
Any game with multiple unit types needs weeks and weeks of playtesting to get it reasonably balanced. During this time things will go wrong and if you have no way to adjust the game in response then you're stuck with something that won't play well. (And not everything can be fixed with stat tweaks.)
Don't worry I thought ahead for this one. I made sure that to do any balancing, all I have to do is simply edit the values on a stats table that contains the stats for every unit.