I like the thunder wolves. Always like to try and throw in at least 1 squad. But with only 2 grey hunter squads you're going to have a hard time with objectives. And I'm not sure you'd have enough power going for a board wipe.
IG could help but with this small amount of guys and you mostly just wanting to run thunder wolves, I'd almost just say do
IG as your primary with
SW as allies. Then take Wolf Lord on thunder wolf, 1 squad of thunder wolves to run him with, 2 squads of grey hunters and 1 squad of long fangs. Also what kinda upgrades and equipment were you thinking for your guys? I my wolf lord with storm shield and saga of the bear on a thunder wolf. Pick the weapon you want for his role. Toss him in a squad of 3 thunder wolves with at least 1 stormshield and they can be pretty mean. Maybe even throw another
HQ in there since space wolves can take 2
hq per 1 slot. So when they ally in they can have 2
HQs 
Maybe a rune priest to run with your grey hunters.