Background Material Evaluation.
Leman Russ was the second Primarch to be located (a "handful" of years prior to Ferrus Manus … and by implication, one of the missing Primarchs), after Horus Lupercal. Raised on the death world of Fenris, Leman Russ was a barbarian - a warrior king who was for a while on his own against the elements of Fenris before rejoining humanity. And he was hugely successful without having access to modern technologies.
The Space Wolves themselves were developed in isolation from the other legions -- alongside the Salamanders and the Alpha Legion -- making up the third of the trefoil of legions held apart from the others during development. Inferno gives no more clues about this, but some interpretation could be made from the fact that they were very hard to raise a legion from Russ' gene seed as the fatality rate was abnormally high.
Following Russ' recovery, the Fang was constructed and from herein, things went well -- at least according to the Emperor and others of the inner circle. In reality though, his brothers held Russ at arm's length regarding him as savage in the same way they might mis-trust Angron and the World Eaters. Savage beyond compare and usually causing vast collateral damage when sent to war, the Space Wolves became a truly independent force bound only to the wolf lord and his absolute loyalty to the Emperor. Good job really that they didn't turn like Angron - the outcome of the Heresy could have been quite different. Overall, Inferno paints a picture of a loyalist son who is the analogue of Angron, but exceptionally loyal and capable.
Legion Rules Review.
The Space Wolves are a legion apart from their cousins in other legions, right down to their command structure and squad complexions. There are several rules affecting the creation of Space Wolves army lists that seriously affect what they're able to deploy and, accordingly, the rites of war they are able to take. Compulsory HQs must come from praetors or centurions. Other consuls are introduced (the priests of Fenris), and there are certain consuls that cannot be taken (librarians, etc.). Coupled with the requirement to have an HQ per 1000pts and the fact that compulsory troops are only Grey Slayer squads (all other troops are designated support squads) contributes to the feeling that the Space Wolves are an infantry based army.
Beastial Savagery provides a WS bonus on the turn a unit successfully charges and counter attack. Balancing this, they must always sweep (but they were probably going to try to do this regardless).
Hunter's Gait provides an extra 1 inch to runs and consolidations. This means their troops are going to be one of the fastest of all the legions.
Preternatural Senses laughs at Night Lords and makes them ignore night fighting, plus grants re-rolls for outflanking and ensures they're not going to be infiltrated closer than 18" by anybody. This is a great boon realistically.
Finally, a Space Wolves HQ must use a new warlord trait table rather than any other. The bonuses in that table are balanced overall, but I do like Howl of the Death Wolf for re-rolling run and charge distances!
Fenrisian Wolves can be purchased by praetors and centurions alike, providing some ablative wounds and even can have feel no pain if upgraded to a cyber wolf (for an extra price). Overall, this is an upgrade that is well worth while in my opinion.
The Frost Blade set of weapons are a nice replacement for power weapons for characters. I like the axe for the +2 S bonus (but might as well take a power fist to be honest!), and the great frost blades for their reaping blow which provides a bonus attack.
Aether Rune Armour is very nice -- providing +1W as well as the usual 2+ save for artificer armour coupled with a bonus for denying the witch. Worth it, so take it.
Rites of War.
The Pale Hunters is highly tailored to the Space Wolves. Not only is there a bonus to reserves, but they get hit and run (at a reduced move of 2d6), and +1 attack for mobbing an enemy already locked in combat. This latter one is huge and speaks to building an army around fast moving infantry. The balance of only having one heavy support unit is good, and fluffy. This is one army that I would not personally like to face, but no doubt I will.
The Bloodied Claws grants furious charge at the expense of always having to charge if possible. The combat resolution gets a bonus of +1 which is amazing when facing off against other legions (Recall that 30k legions have no ATSKNF rule!). Plus, they get the aforementioned howl of the death wolf as their guaranteed warlord trait. This rite of war is superb in my opinion. And yet another very powerful close combat rite of war that I don't really want to face. The restrictions are tough in the sense of no immobile, artillery and slow and purposeful units -- meaning no drop pods. That said, of course, dread claws are not immobile, so they'll certainly do for this rite. I actually fear facing this type of army build. They're going to be very good!
To sum up: the Space Wolves are infantry based. They are fast (particularly grey slayer squads -- reviewed separately). They excel in close combat. Their rites of war are meant to help mob up on opponents (pale hunters) or be a bit more tactical with hit and run coupled with resolution bonuses (bloodied claws). This calls for multiple grey hunters squads backed up by those toting assault weapons and very few (if any) heavy support choices beyond dedicated transports. I think several land raiders, rhinos, dread claws and the like, all loaded up with chunky squads will be common with the Space Wolves. Indeed, the "in your face" way of playing here is very much emphasised by their overlapping rules that can provide very nice bonuses for this kind of play style. Fast, furious, and close combat. Even Angron would approve.