Its got to have alot of twists and things to keep sumone interested. It can't just be pure fighting all the way through. Its gotta have a story to it and has to be realistic, not sum cheesy rambo type thing. I think number 5 on that thread has alot you can use, car chases, raids, gunbattles.
I dnt really know much about the best units that are available but i think to make the best, you have to use the best.