I can't answer all, but…
Municipalities are considered creatures of the Province. I believe at any time the Province can (with a majority vote) dissolve a municipal government. Technically, they don't unseat the mayor, but the entire government. And because a municipality cannot lack a government, an election is instantly called. Not sure what happens in the interim, but it'd be a MUCH shorter campaign period. As an alternative, I believe they can also instate interim seat fillers.
Re: Tools; I suspect some sort of super-majority vote of non-confidence amendment to the City of Toronto Act, i.e.; if ⅔ of council votes to unseat Ford, it would authorize the Province to vacate the seat (and not the entire government).
Hudak is toast if he sticks up for Ford. He might still try and stick up for Doug, but why waste the energy and risk the potential scandal if Rob gets taken down by the Law.
Because I'm a politics nerd, I'll chime in again.
The constitution of Canada only sets out the governance of Canada and the Provinces and Territories. This effectively means that provinces are free (under the constitution anyway) to organize the efficient governance of the land and people within as they see fit. Really, if they wanted, there could be no municipal governments at all, no mayors, nothing. In Ontario, however, the province has decided to divide into 430 or so municipalities, and some regions, and defined the form of government for all of them. The province also delegates some responsibilities and powers (like property taxation and bylaw development) to the municipalities that they've decided are better run by those municipalities. All of this is set out in some detail in the Municipal Act:
http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_01m25_e.htm
Because Miller was the man, he managed to convince the province that since Toronto was so cool, they deserved special treatment (particularly since they had been so screwed over by the province by amalgamation... Ever wonder why Toronto got forcably amalgamated but other dual-level municipalities like Halton didn't? Look at where the PC MPPs were from at the time) so the province gave a bunch of extra taxation powers and other responsibilities to Toronto in he City of Toronto Act:
http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_06c11_e.htm
The upshot of all this is to say that what the province giveth, the province can taketh away. Since the province has set out in its own legislation how people get elected, and what positions they hold within those government, the province can go ahead and do whatever the heck it wants to remove or retain those people. Note that for the purposes of this paragraph the "province" doesn't mean the governing party, it just means that whatever rules come out of QP at the end of the day is what happens inside municipalities.
So, if the province wants to remove just Ford through a special Act, it can. If it wants to remove the whole government, it can. If it wants to appoint a caretaker homicidal robot MayorBot, and it goes through parliament and the Lieutenant Governor, it can.
That being said, there is only so much time for things to happen at Queens Park. The reason Wynne wants to only do things with Unanimous Consent isn't just because she doesn't want things to be contentious or to use up political capital on it, it's because if this goes through the whole process, then it's likely that something that she actually cares about won't have time to.