Depends. Decide where and when you want this to represent. Fdo some research to find out what units were there and what style lettering they used. Dragon usually gives you this info in the instructions, don't they? This should also direct you to any figures you'll be adding.
As to tank riders...is this a hot zone, i.e., are you implying there is action nearby? If so, tank riders might not be the best choice for figures, since high on the baclk of a tank they'd be quite exposed to small arms fire/snipers. Troops advancing on the alert might work better.