We still need to do a general stealth pass, where we see which weapons shouldn't be drawing attention, such as killer46 silenced uzis.
But on having someone fully focused on stealth, we haven't tried having a dedicated class yet. A couple of us did find on single player it can be busted if the character just doesn't alert enemies ever, clearing them slowly one by one without any risks or general downsides, but it being nearly irrelevant in co-op, the main focus of the mod.