Yes. You can insert both NVG and thermal vision into the helmet, which works incredibly strangely together. Everything is terribly bright and pixelated.
I see the solution to the problem as making ONE slot, into which you can insert either NVG or thermal vision. Thermal vision also allows you to use collimator sights if they don't have batteries.
I can't say anything about head protection, I've never been hit in the head in a dozen raids, but my stomach consistently dies every raid.
I also apologize for any misunderstandings, I use Google Translate from Russian.