Most games will split along the following lines:
- green vs. tan
- analogue vs. digital
- NATO vs. other
They also rely on, "predominant impression". So if someone were to glance at you running by and said..."that guy is wearing green"...then you'd be classed as being on the green team.
Black belt/boots/balaclava/gloves/etc...is not going to mess that up.
A tan chest rig on a Woodland/DPM head to toe setup...isn't really going to confuse everyone in thinking that you're on Tan instead of Green.
So...I think most people go with what the BDU's are and ignore the rig (unless it's vast like an MBSS/CIRAS).
So in that sense....don't worry so much about the rig.
BUT...you'll probably find that OD is a lot more flexible and efficient in field games vs. a black rig. For that matter...a TAN/Coyote Brown rig might be too.
You may find that eventually you end up with a "Green" setup and a "Tan" setup....either because you set things up one way for field games and another for CQB, or you prefer to be on this side or that of a game, etc...