High evasion shouldn't be an option for jobs that wear heavy armor. I was under the impression that this was part of the reason why jobs like THF/NIN/DNC all have better evasion to offset having to use light armor.
Samurai wears heavy armor and they have B+ evasion, natural Seigan/Third Eye and A- parrying too. I'm just asking for B+ evasion seems fair. Also before ToAU, DRG couldn't wear heavy armor, only scale and leather like RDMs yet NIN could wear Royal Knight Armor/Chainmail and Haubergeon type stuff which is heavier armor than DRG and they had A- Evasion.