[Kozzie]

I'd have to say go Coyote Brown for your rig, it fits better with both tan and green than green does IMO. As previously mentioned helmets are easy to paint, get a tan helmet and spray a little green on it or vice versa. You could even mix it up by getting a tan rig and putting both tan and green pouches on it. This will both break up the your silhouette of a big solid coloured blob, and make it fit with both green and tan based BDU's. A lot of people would probably wince at the idea of mixed coloured pouches and gear, some will even only buy pouches and rigs from the same manufacturer to make sure the shades all match exactly.... I'm not so picky.

For camo pattern perhaps where you intend to play the most should dictate that, after all the whole idea of camouflage is to help you blend into your environment, not to look cool. Most camos will have a woodland and arid variant, you may want to take that into consideration when choosing what to go with if you want to use the same pattern for both your green and tan set-ups. I personally like old school US Woodland and Tri-colour desert. They should both be easy to find surplused at good price.