Slitherine

Do I have to conquer every city hex to culminate more requisition points for next scenario?
How to increase requisition points?

It is not stated in the manual or brief in tutorial I believe.

the more you do, the better off you are, but as long as they are primary ones, the no you don't have to, but i would

Doing more than strictly necessary to achieve your objectives will improve your glory ("score" in the game), but will not increase requisition points. You need to fight and win with what the "high command" gives you.

or cheat like hell and use the editor