I assumed you travel as a couple and AB (window and isle) feels more private for one of you who can also enjoy window views.

Naturally, if both of you you care more about direct aisle access, D&G are the seats for you.

4DG would be my first choice (bulkhead cubby holes seem to be slightly bigger) and 5DG seats which are comparable.

​​​​Front C section is quiet and more intimate and it's a big advantage especially on night time flights, there is not so much traffic to the lavatories (they are in the galley behind you), only FAs going to and from the F section.

Enjoy your flight!