No pro, but I'll give my 2 Cents:
You've got a pretty well rounded setup here, the only thing I wish you had was
MoTW in your
GH squads. You've got a good model number at the moment, so the Mark is optional really, but otherwise, at 1k pts, that's a good list.
Up to 1500?
I would add more
GH's (maybe leave space for
MotW? If you want, your army, your preferences). Gonna need more
WG for your
GH squads, so that means more
PF/combi-meltas...
Try dabbling (if you've the space after your core units) with maybe some more shooty guys (shooty dread? More
LF's?) or some fast attack (
TWC?).
A good hammer could also be a squad of Termie
WG in a landraider, but that's WAY expensive (I think that would be the only addition if that's the way you chose).
Also investigate a Lone Wolf (if you like them). My personal combo would be Termie armor/ Chainfist/ Storm Shield, with 2 Fenrisian wolves for more survivability.
Like I said, take my advice with some salt, because I'm no pro either. There's some very good dakkaties on here that can do far more.
May I suggest you investigate these:
http://www.dakkadakka.com/wiki/en/Space_Wolves_Tactica%2C_5th_Ed/09_Codex
http://space-wolves-grey.blogspot.com/
If you're not familiar, get familiar. You'll appreciate what they have to offer.
Good luck.