Hi Banjo,
It sounds like you are in a lucky position - to have the cash to do this. There are many out there with big loans and no job.
If I was you start by flying for fun - after all you can (by the sound of it) afford it. I would do the ppl (as quickly as you can) and then see how you like it. Build some hours up, but be structured about it, practice the navigation, handling, emergencies etc and remember to enjoy it too. If you still want a career from it (and I bet you will) start to do the exams for the commercials. and then the flying course. Then hour build, then instructors etc....
If you take it one step at a time, and then find that you don't like it, can't get a job, run out of cash, then you still have your old job to fall back on. And you will able to continue flying for fun.
There is no one in this industry who can predict what the job market will be in a years time - it is a gamble. But it can work out for you, just don't hold your breathe. It took me 4.5 years from starting my ppl to getting a commercial job, and that was quicker than many others. I know that makes the full time course sound more attractive, but unless you are certain you can get your old job back in a years time, to me at least, it would be too big a risk.
Don't worry too much about the maths, it is not as advanced as the O level maths I did. If maths is still a worry, I believe the open university do an introductory maths course which I hear is excellent.
If you want it - go for it. I did and I have been lucky - I am flying that dream!