i would like to see more Specialized perks. but one for a certain unique weapon seems a little useless.
hmmm. i wonder if there will be a unique grenade machine gun
Mininuke Machine Gun.

Anyway, specialization perks.
Hmm how about:
Grenadier
You have a greater chance at finding grenades in ammo boxes and lockers, you know how to sweet talk merchants to sell them cheaper to you, and you get a +10% damage with grenades.
Twitchy Gunslinger
You get a faster rate of fire with all one-handed weapons excluding SMG's.