Funny that you post this query now. Just yesterday I finally got around to dealing with that area.
I didn't want to cover up the angle braces. However, where those angle braces touch the bottom of the boat and the new deck that I added, was a concern.
When I added my flat deck, I filled the under areas with blue foam. I extended that foam all of the way out to the inside edge of the gunnels. If I drop anything; it only falls as far as the outer edge of the foam. i.e....it can't slip under the deck.
So, the only issue was one of appearance. Yesterday, I glued some camo'd 1/2 x 4-inch strips lengthwise along the braces. I chose to use construction adhesive glue instead of screwing or riveting the pieces onto the boat. The reason that I chose glue was that the area that the strips covered was the same area on the braces where the bends are. Those bends are there to created a strong angle. Driving screws or rivets in them, it felt to me, would weaken the very part that I want to be strong. The PL brand construction adhesive appears to have dried solid and should hold my strips on well.
If the strips don't hold up, I have a fallback idea using small aluminum strips to fortify the joint.
With the long strips abutting the braces, small cavities are formed. The foam makes up the bottom. I can see those cavities having value for storing bottles; tools, and other objects.
I'll try to post a picture, but the boat is in the barn and I don't intend to go back there for a day or two. Hope this makes sense.
richg99