With Channeling, I get the boosted Agility. And at the force I can, in practical terms, summon for regular use, my skill will be better. Between Aptitude and Improved Ability...
Remember, I split my Magic between Adept powers and Mage stuff - Force 4 is all I get before the Drain gets Physical, unless I'm misunderstanding the rule - which I suddenly think I might be.
Still, with the limited dice pool, high Force spirits are generally going to be out of reach.