Bit of a work in progress and creating thinking.
The core of the force will be Grey Hunters. For each unit, I hope to attach a Wolf Guard as proxy sergeant, in Terminator armour. Sadly this means they cannot ride a Rhino! The other dilemma is needing 10 models to field 2 assault weapons. Including the Wolf guard puts the unit to 11 models (12 transport slots). This is also annoying for Space Wolves, as their Drop Pods uniquely only fit 10. Id have to take 8 Grey Hunters plus a Wolf Guard to fit a pod.
My HQ will most likely be a proxy for Bjorn. Rock hard Iron Hands dreadnought seems the most suitable path to take!
Elites are oversubscribed. I'd like at least 1 other Dreadnought to back up Bjorn, but need to use a slot of Wolf Guard (half as Morlocks, half peeled off to Grey Hunter squads) and another is likely to go onto an Iron Priest. However, I am tempted to simply model an Iron Father out of a Rune Priest or Wolf Lord and proxy it to death.
Fast Attack. At best, a couple of Land Speeders. Half-tempted to make some combat servitors as wolf stand ins though.
Heavy Support. 1 or 2 Vindicators and a Land Raider. The heavy steel is a must!