no death 3 is not certain death lol. the losses are moderate. I'm currently on turn 58 in my mictlan game, and have only had to leave one province due to pop loss. my blood income is 160 on a very bad turn, and more likely over 200. my dominion is on par w/ the strongest in the game. my income is fine. And i've had one barbarian attack all game - that's w/ misfortune 2. I think taking misfortune 3 is definitely a no-no though. As well I have no soul contracts and only one vampire lord, who is actually patrolling not summoning allies
Now, Storm knows the endgame much better than I do, so I may well lose, but that will not be the fault of Mictlan.
And, again, while you can keep unrest at 0 w/ 2 bloodhunters, that does not in and of itself make it the most effective use of your resources. so what if my unrest hovers around 40-50? that's a 10% blood slave loss only from what it would theoretically be if I patrolled.
Mictlan is about the least likely nation to experience dominion kill in the late game. And even early it is easy to avoid unless you're a total moron.