Even under bog-standard canon rules, Mort's a better ectomancer than Harry. His skills might be a point or two lower since Harry's a much higher-Refresh character, but unlike Harry Mort has relevant focus bonuses.
And, if so, they're only higher in the later books. Harry is Conviction-focused, which isn't that important for thaumaturgy. His post-Storm Front stats are only Good Lore and Discipline. As of the last few books, yeah, he's probably got a Superb in at least one of those (and probably Fantastic Conviction) but that would have taken him quite a while.
If Mort has, say, Great Lore and Discipline, Ritual (ectomancy) gives him two focus item slots. If he has a +1 control +1 complexity item, he can draw one shift of power per exchange with no risk. Plus, he probably has Ghost Speaker to do some basic 'ectomancy' without even having to use a ritual (yeah, he doesn't have that in OW, but...)
So he's definitely better at ectomancy than early-books Harry.
(And it's probably even more lopsided, since a lot of the stuff Mort does might run into a "Not So Subtle..." aspect compel for Harry. He has the Spirit evocation to do veils, but until Changes, he really doesn't.)
Like I said, the rules are assuming that a focused practitioner is not just a wizard who is specialized in one field, but someone with less overall magic,
And that does seem to be the general rule in the Dresdenverse. There's one possible exception but (SG SPOILER)
when we meet her, she's a Denarian, so that's kind of unreliable data as to what Focused Practitioners can do.
Mort is impressive, but I think a full Wizard who spent all his time and focus into ectomancy would be better.
But ultimately, if you want to create a character like the one you are looking for, you'll have to do a bit of work on tweaking things, because the focused practitioner from Your Story just isn't the same as the kind of character you have in mind.
Yeah.
Channeling doesn't technically allow it, but the real mechanical issue IMO is the Refinement pyramid. You could at least get to "+1 power, +2 control" or "+1 control, +2 complexity" before running into problems with that though. That, plus focus items, will get you pretty far.