started playing this last night, i know it's still being patched etc. and I've looked elsewhere for answers with no luck.

Petros dead = mission end. there's no way to stop this, am i right?
Move HQ (to try and address the above problem) can only be done if the arsenal box is empty? so if I want to move him into a building to stop the helecopters killing him I need to empty the contents onto the floor, then into a vehicle then move the HQ and unload the vehicle? if there's an easier way, can any of the purchased vehicled perform the easier way?
To help mitigate The fact that I'm 'spotted' pretty much all the time, making undercover useless, then this causing me to get slaughtered by enemies impossible to see while I'm wandering the hill sides on foot, which i am used to on most sandbox scenarios, Is there any easy way to disable the grass that is more of an issue to players than AI? I like a challenge, but one that i have a fair shot at would be better.