With all spellcasting, there's a skills component -- focusing on boosting those skills really high and then marrying them to a very narrow, focused spell talent, would get you the end result you're talking about.
Mortimer Lindquist is actually a great example of this -- as a ectomancer, he's a bit narrow in what he can do, but he can do that stuff *really* well (once he gets his belief in his magic back). Narrower powers, spiked skills -- that's how you get it.