Hm. Here would be my ideas, in roughly reverse order of your bullet points:
1: Pick a different Law - and, potentially, aim for the shades-of-grey areas rather than actual lawbreaker territory. Consider, for example, a paleontologist with a bit of necromancy - who got into that not as a path to power, but as a means of asking "What did this creature look like / act like?" It's not technically lawbreaking, because it doesn't involve humans, but it could certainly lead to some of the same temptations / warden problems.
2: This seems different enough from Dresden right here. Since when has Harry valued politeness? Normally he's mouthing off to everything in sight.
3: My personal gun knowledge is what I can find on wikipedia, so just picking the same choice of handgun isn't a similarity I'd even think about. That said, see also point 5a.
4: Clothing works fairly well here; my tendency is to use either clothing or some form of luck charm.
a: Consider someone with an enchanted business suit, for example - it makes as much sense as a long coat, and suddenly gives the character a very different feel.
b: Another sensible direction to go is to layer enchantments on top of real armor (which you then use the long coat to conceal so you don't get funny looks from the police).
c: Or you could even pick up a cheap Item of Power - one character I made had an iron-scaled snake-skin leotard made from the hide of a long-dead daemon. +1 for concealability, +3 from some reasonable catch (cold / ice in that particular example), and you can get, say, Inhuman Toughness & Recovery plus Echoes of the Beast, all for a single refresh. And you can still make it an enchanted item, too.
5: Fire is useful, yes. But there are a lot of ways to use it differently from Dresden.
a: Consider, for example, what would change if, instead of a blasting rod, you used an antique flintlock pistol (say, one of the really decorative ones with the dragon-mouth at the front and whatnot).
b: Or consider how it'd work if you used fire as your primary defensive element, burning or melting incoming physical projectiles, blocking magical attacks with purifying flames, and causing melee attackers to flinch away from the searing heat of your shields.
c: Or consider a caster whose primary focus is on the metaphorical uses of fire, rather than direct physical applications. Such a character might well be dancing on the edge of the fourth law of magic, using spells that inspire or infuriate or inflame passions... but, like the love potion from Storm Front, never quite strip away free will... really, I swear, please don't kill me Mr. Warden...
6: Again, I'd probably pick out a thing or two that made my approach to Spirit different from Dresden's. On the other hand, by the time we get here, that may not even be needed; a few similarities are certainly acceptable. Possibly just not having the same brute thug approach to magic would be good enough - if you don't need to buy off a compel every time you use a veil and want to see out, for example, that's a fairly notable difference right there.
