Playing pro-Carrion devil's advocate: The only saving grace is that it doesn't need LoS to strip immunities and it can fly, making placement somewhat easier ... hide in or behind terrain, enjoy the 8" pie plate. I wish it's Wk were a little higher for this purpose, but 5 isn't bad. Too bad it can't Perch like a Vulture. 6 of anything to cast, so no need to commit precious high cards and suits. Hard to Kill at least stops the one-shot kill. I don't foresee ever going for the 2+Slow severe w/ magical poison, though. Hell, even sticking it's beak out for a ranged attempt seems dodgy. Df 4, Wd 4, no other defensive abilities, it'll fold like a wet napkin to pretty much everything, even on weak damage flips.
Otherwise, yeah, keep him with your crew, keep him hidden and safe, enjoy the healing flips assuming you don't need the corpse counters. Sounds good for Kirai (who doesn't need counters) and Seamus (who can do without more than a few and really needs immunities to disappear). Hard sell for McM and Nico, both of whom need counters and other special forces (Rogue Necro, etc) to really shine. I could see him being useful in a defensive role; set him up somewhere safe, put up Diminished Resistance, force the enemy to advance into it to claim an objective.