I would say do your PPL and ATPL theory here before going out.
The PPL theory is not too hard, and you want to make the most of the good value hourly flying rates (after all that's why you are doing it there and not here) so you don't want to be paying for accoms and living costs in florida when you could have done them here.
With the PPL flying, check out some of the other posts on the forum about florida schools, the general feel is that you need extra time, there are extra costs and it ends up not being far off the cost in the UK.
ATPL theory can be done distance learning for £999, or for about £3000 in a classroom I think? Which is much cheaper than 6 months into Florida (unless you work as well, but 6 months is full time study so it's hard to say there).
I would say do the above before you go in the UK, then complete your training in florida if that's what you want to do., i.e. CPL, I/R, MEP.
Low hour jobs are very hard to come by these days, there are too many pilots, low and high hours, and not enough jobs, but that is not to say it is not possible to get a job, just difficult and needs a bit of luck. There are options, like bush pilot jobs, they will take low hour pilots, check out some airlines in Maun (there was a programme about these pilots on Dave recently, really good, check it out).
I will add here that my info is from my research into this, as I am in the same position as yourself, saving up for PPL training and then ATPL, and then taking a loan to pay for the rest.
If any of my info is inaccurate, please correct me other forum posters.