Remember that you only get to Share Spells with your animal companion if you go beastmaster. But you do lose a caster level and a level of wildshape.
Beastmaster it is technically better then Wild Cohort in stats, you get one animal companion at your Level +3 and one at your Level. Maybe with nature bound you could make both be at your level +3, but thats probablly arguable.
Wild Cohort or the Initiate of Nature feats don't give you Share spells. Initiate of Nature beats the crap of Wild Cohort, but the later is simplier and therefore should be easier to get away with(without having to find the animals and fascinate/rebuke them).
That said, you can share spells with your main animal companion and cast spells like Animal Growth and the excelent Nature's Favor (Druid 2 swift action, SC) in your other animals, and they would be just as deadly.
And you could always summon some additional Dire wolves