There might be a solution to keep both 3rd and 1st person.
A while ago i played on another arma 3 life server. on there if a gunshot was fired, everyone within a 300 meter area would be forced to 1st person for atleast a minute (the longer the firefight lasts, the longer you will have to use 1st person).
However i do not know if this is possible to recreate without using mods, it would be something to look into.
This way combat situations will be played out in 1st person, while everything else, (such as driving, flying and recource gathering) needs the 3rd person view in order to work at its best.
hopefully something like this can be implemented to keep both 1st and 3rd person fans happy