This

Most of what you are trying to accomplish has already been done. Unless you enjoy reinventing the wheel, then go take a look at the grids on aerocrew news. They have decent comparisons on all the airlines and will give you an idea of how the regionals differ with respect to some of the variables that folks have mentioned here.

If you are looking for a flight school like you mentioned in your original post, then narrow down your search to a few regionals you would be happy to spend a long time at and then research if they have any programs that will help you pay for training and what schools/universities they have agreements with. Choosing a regional will always end up depending on what is most important to you. The big three people tend to look at are (in no particular order) base location, QOL, and 1st year pay. Some folks also take a look at the iron the airline flies as well.

Best of luck with your research and trying to plot a path forward.