Welcome fellow Oregonian!
Looks like you have a pretty good build list going.
For gas blocks I stay with simple low profile steel gas blocks. If the barrel comes drilled and pinned with a gas block, I use the one included. I stay away from aluminum gas blocks. Gas tubes are pretty straight forward, but lately I have been liking nitrided gas tubes. No real performance difference, I just prefer the black of nitriding to the shiny bare stainless.
I've used A2 flash hiders, Seekins Precision flash hiders, and the KAK Slim Flash Can. All have worked well. I've shot my brothers 9mm and 5.56 AR's with muzzle brakes. Personally I don't like muzzle brakes, or shooting next to muzzle brakes. It is personal preference but the concussion from a brake gets annoying after a while and can be even worse in a shorter barrel or enclosed spaces. On my 10" 300 Blackout pistol I use the KAK flash can and it works well in diverting flash and concussion down range.
Some build to replicate a military rifle. Some build a rifle out of spare parts. There probably a million different combinations in the AR world. That's half the fun and why the AR has earned the nickname "barbies for men".