The designated hot and neutral wires are a good idea in my opinion,, I know some differ in opinion.. so
for the wiring.. you use more wire, though, in the long run gives you peace of mind (knowing less chances of shorts)..
I've wired and rewired several different boats using your method and have never had a short,, where-as, I have had a hard time running down a short on others boats where they have spliced everything together
.. most of those shorts would be either under the boat (Pontoon boats floors) ,in a small console or under a dash, where it looks like a spider web ..
and no room to work..
Your wire chase did help you out with the wider than 60" width,
and when covered you'll know exactly where the front to back wires are run.. only have to mark where the cross wires run to everything,, as to not staple through them when applying the skin, if you use a stapler or pin gun to help with the application of the skin..