Sutto,
As far as feathers:
5" will be fine. You may have to "slightly" adjust your jig a hair to reduce some of the helical wrap, but you will be fine.
Use fletch-tite PLATINUM in the silver tube.
All screw-in blunts/judos/hex head/broadheads are fine. The only ones you want to diameter-match for 5/16" are the field points, as this affects how they pull out of targets.
You should use a GOOD two-part quick-cure epoxy to seat the inserts in the shafts...and if available, buy Easton SUPER 3D nocks for them, as the throat diameter is just a hair larger and fits your string better than the standard wheelie nock that will come with the shafts...
As far as the carbons themselves, a lot of guys swear by these "front-weighted" carbons with 200 or 300 grains up front...
However, my personal opinion is that massively-weighted carbons have a higher trajectory "arc" than a shaft that is properly spined to the bow, and bareshafts with a single 15-grain insert and a field point from 125 to 160 grains.
This is NOT to start an argument guys...this is just my opinion, and I LIKE to shoot out in my yard at distances way over 60 or 70 yards, for fun...and this is my opinion of the characteristics of flight associated with the super-high FOC concept...
So Sutto I would try a 1/2 dozen beman 400's, a 1/2 dozen beman 500's, fletch 3 of each, bareshaft 3 of each, and then shoot to see which tunes the best.
Or if they'll let you, just buy a few of each...you get the point, anyway...
I wish you well on your hunt!!!
Take Care,
Marc