I think the addition of head mounted thermal optics is a great idea. But, I think it may be a bit OP in pvp. Like in a wasteland server or a life server. In situations like those you probably do not have stealth uniforms therefore you can be easily spotted. So it is much easier to chase someone through the jungle with the thermals on than if they weren't. Knowing where the enemy is is extremely important, that is why they use drones so much on I&A servers. You can respond to what you see but not what you don't. Thermals make heated objects stick out like a sore thumb. But I think it isn't as OP when fighting AI.