Sorry for that english, is not my first language so sometime it's not completely clear ... just to clarify for me the Backseater is the Pilot ... Frontseater Gunner, to keep it simple.
Well ... Backseater is the main Pilot and Frontseater is the Copilot/Gunner... So technically the main station will be the Backseater. In the Hind in MP you can't enter the frontseat (gunner) unless someone is already in the backseat (pilot). So I don't know if they plan to remove that restriction (I have some doubt) for the Apache... But in the Apache the Pilot can almost do everything the frontseater can do so that's a good thing at least.
I'm pretty sure ground impacts effects are not related to a specific module. And for the FLIR is already a good thing that they are coming with something new for the Apache, don't expect everything to be like the "real thing" at launch ... My opinion