For trout fishing, I tend to catagorize my boxes.
1. Small swing leaf box holds all my nymphs and scuds
2. Mid size Orvis compartment box for bigger dry flies (size 16 & up). This box contains mostly Adams and Caddis Fly type patterns.
3. Small slit foam box for wet flys and soft hackles.
3. Small slit foam box for terrestrials.
4. Orivs foam box for streamers and buggers.
5. Small slit foam box with small (size 18 and below) dry flies and midges.
I only carry the terrestrial box during the summer and streamer box in the fall and winter. The others are always in my vest.
Since I drive up to four hours one way to go trout fishing I tend to carry everything with me. However, I have put together a minimalist box and carried that, but I also have the others back at the truck if needed.
" If a man is truly blessed, he returns home from fishing to the best catch of his life." Christopher Armour