Instead, I would have an improved battlefield-range "radar mode", and a portable detector in the secondary hand to enable its use.
IR googles should only allow for detecting "opened" energy sources (living beings, engines) under dark, partially covered, or smoky conditions.
- If the game engine allows, thin walls and doors would be passed through (those with a penetrating resistance of 1?).
- They would act as if the gamma setting of the player's monitor had been changed (only as far as energy sources are concerned), and that's they seem to do as for now.
- Dead body shouldn't radiate as much as currently.
- Googles could be hampered by fire fields and disabled by stunning grenades and other nearby IR flashes.