Absolutely. Sounds like you've got a great plan for dispersal of any excess.
Agreed. Not to stray from Jim's search for opinions on fill coats but I've often wondered about people's trim preferences... I think Canoecraft recommends inner & outer gunwales at 3/4 inch each for a total of 1 1/2 inches. Right or wrong, I've been using 1/2 of that (3/8 inch each) and the boats seem plenty strong enough.
Of course, I've yet to hang a seat from the gunwales but, when I do, I'm not planning on using a 3/4 inch gunwale from stem to stern.
How light has anyone else gone on some of this stuff?
Gunnels are one of the biggest potential areas for packing on extra weight (I think I have said that in every build thread I have done), so I am in total agreement with this sentiment.
Personally, I have settled at 5/16" x 5/8" for my solos and 3/8" x 3/4" for tandems ... granted you have to consider how you are going to use the boat, there are times you need more gunnel.
If you need to hang seats, I like to just add some width in the area where the seat goes, retaining a lot of the weight saving ... having said that I have also moved on to using seat cleats, I find them easier and cleaner to install.