I have no specific experience of this but to take your second and third points, the repayments of the loan become part of the levies. People who want to pay in advance are missing the point – loans are their to spread the pain. People who fall behind on their levies will be subject to the same obligatory penalty rates and should be quietly thankful that you didn’t go down the route of a special levy.
But there is a bigger issue and that is getting as many people as possibl;e to understand what is happening.
You need to get a strata loan specialist (like our sponsors Lannocks) to come to a meeting and explain what you are doing and why. Then you need to send out a newsletter of some sort to those who didn’t attend, again to explain what you are doing and why.
Then just get on with it.
You have a legal duty to maintain and repair common property. It doesn’t matter whose fault it is or even who can or can’t afford it. You have to do it and the Owners Corp has to pay for it by whatever means the majority of owners feel is best.