I think everything should be viable, yes there can and shoulb be slight inbalances but not too big ones.
Some people say that there should be better weapons and weaker weapons to balance the augments but that does not realy work.
Fragger has better m4 loadouts than he has K-121 loadouts. As a weapon the K-121 is just ok and very hard to use, while m4 is almost like god mode. Yet fragger does not get almost any augmets that benefit him that much with K-121.
Sawbones used to have very unbalacned loadouts. Like Crotzni with the best augments.
Now when SMG-9 and Crotzni are more balanced, their loadouts are also bit more balanced.
However there are loadouts with good and bad weapons that have terible augments.
I would actualy like if they separated the weapons from aument cards. So players could choose what smg sawbones could use (still the current 3 options only avaivable) with some loadout card with some play style benefitting augments.