First off, don't run heavy unless you are a healer.
Both stamden and necro can be run with NMA/Fury, these classes don't synergise too well with most popular proc sets anyway.
3 infused jewelery, 1 cost reduce 1 wpd 1 recovery glyph, you can run lava foot soup food on both just out some points into hp.
Should get you to about 2k ish recovery which should be plenty to sustain.
Stam toons already don't scale too well with max Stam so shackle and bone pirate are kinda weak, especially in no cp where you have less Stam to begin with.
If you Don have access to fury you can substitute it with something like seventh legion, it's pretty easy to get, until you can afford fury.

Forget about heavy armor in pvp. There is no heavy armor meta. Heavy armor meta was when blackrose gave resources on being hit. Everybody who claims "heavy armor meta" has minimal understanding of pvp. You're not gonna be sucessful running 2 sustain sets in 5 heavy. And if you're doing good with 5 heavy magicka setups in bgs you probably are in low mmr. I can't imagine killing someone with half a brain wearing 2 sustain sets and missing out on 5k pen and spellcrit.

For stamina it's actually very simple, there are no decent proc sets and stacking high weapon damage will make your vigor heal for a lot, medium armor amplifies that with the weapon damage bonus, plus you can avoid a whole lot more damage with cheaper dodge rolls and sprinting. Plus you get free major expedition from the medium armor skill which will probably be up all the time since in in battlegrounds you're always taking some kind of aoe damage. Heavy armor cannot compete with that lame 8%healing bonus and a few thousand extra resistances with health.

One universal setup across all 6 stamina classes would probably be 5 medium 2 heavy bloodspawn,new moon acolyte nirnhoned maul frontbar,infused jewelery with weapon damage glyphs,bone pirate with pack leaders bone broth food and either potentates snb or masters bow backbar with serpent mundus. Giving you good overall damage healing and stamina sustain and some defense.