How would a say... 3k or 4k Space Wolf list look like?
Well it would be a personal thing really, and could depend on what minis you have and what you like to see on the table, but a good start to base a list around are the Great Companies.
At 3K I usually take at least 2 beefed up GCs and have used 3 of differing size as well.
A list I've taken before has looked something like this:
GC + 2 Long Fangs + 2 Grey Hunters
GC + 2 Long Fangs + Wolf Lord
GC + 2 GHs
Blood Claws + 2 BCs + 2 Land Raider Crusaders
Swiftclaws Attack bikes
Whirlwinds + Hunter
plus sundry (150 point left over??) I forget....
I could swap out the Fenrisian Wolves for a Land Raider formation too.
The GCs are hard as nails formations and the Blood Claw pack is too and acts like an inferior GC as it suffers from the Unblooded rule. Don't forget the Pack Mentality special rule. The list above is quite defensive and tends to hold ground well.