Is the fate system the best for the book series

[Hick Jr]

I'm kind of shocked that you're only at ten shifts at 30 refresh if the guy is someone all your characters are meant to fight. Belial666 has a character that's knocking off 16-shift evocations at about half that refresh level. I'll reiterate- Extended evocation blocks, enchanted items, and summoned mooks are your friends here.

[Deadmanwalking]

Even at 'only' 10 shifts, a remotely capable combat-Wizard should destroy 7 Refresh PCs with a flick of his wrist. Or (like any Wizard) die like a punk if he fails to get his magical defense up in time. Wizards without magic are fragile as hell...as it should be, given how that sort of thing is portrayed in the Dresden Files.

[Hick Jr]

Yep! Assuming Superb conviction and rotes, that's six mental stress boxes equals
-one 10 shift block
-extend aforementioned block by 10 exchanges
-4 Weapon:10 accuracy 10 blasts for one stress each. 

Wizards are squishy until they get time to fort up. And I agree. Wizards have to have some weaknesses.

[Sanctaphrax]

I'm kind of shocked that you're only at ten shifts at 30 refresh if the guy is someone all your characters are meant to fight. Belial666 has a character that's knocking off 16-shift evocations at about half that refresh level. I'll reiterate- Extended evocation blocks, enchanted items, and summoned mooks are your friends here.

Bear in mind that Elena benefits from a highly optimal homebrew Sponsored Magic and a house rule that lets Lawbreaker add to spell power. 30 Refresh guy presumably didn't get either of those perks.

Though people tend to think the Lawbreaker thing is an official rule, so who knows. Maybe he got Lawbreaker to power after all.

Since 30 Refresh guy was a necromancer specialized in mind control, he probably had 6-10 Refresh invested in Lawbreaker. Plus 2 in Sponsored Magic. Plus 7 in the Wizard Template.

So we're really "only" talking 11-15 Refinements here, even assuming no other Refresh expenditures.

[Aminar]

And by Suboptimal you mean flavor. 
I mean, how else do you pull off a Linkin Park cover band lost child of Kemmler necromancer who's pulling off a Darkhallow in Disney World?

Although come to think of it, they might have had 8 or 9 refresh by then...  It was a long time ago and that session got cut in half due to Migraine inspired projectile upchucking.  Is a bit fuzzy.
And notice the darkhallow bit(That does keep one busy...  He was relying on fetches to keep him safe and they frankly gt outwitted(who knew some of my PC's knew about the tunnels below Disney where the Giant Purple Dragon doesn't fit.)
Granted they were supposed to succeed, but not so easily.

[Deadmanwalking]

Yeah, 10 shift Evocation isn't at all unreasonable for a -30 Refresh guy with a lot of Lawbreaker (probably -6 to -8 worth of Lawbreaker) who's focused on Thaumaturgy.

It's also more than sufficient to destroy most Waist Deep PCs. Especially if he's got Lawbreaker (First) which I'd argue he really should.

[Aminar]

Yeah, 10 shift Evocation isn't at all unreasonable for a -30 Refresh guy with a lot of Lawbreaker (probably -6 to -8 worth of Lawbreaker) who's focused on Thaumaturgy.

It's also more than sufficient to destroy most Waist Deep PCs. Especially if he's got Lawbreaker (First) which I'd argue he really should.

No.  He'd avoided that one so far.  Largely by mind controlling others to do his killing.  And being a cover band, leaving dead rodies behind is far less fun than kidnapping the hot ones via mind control(in his mind)