I now understand that you are on the fence between 4 professions and not necessarily trying to pursue all 4. I will give you my insight on them based on my own research as I have considered all of those options at one point or another.
I am in Canada and so job markets may be very different where you are. Where I am, a teaching degree is pretty much toilet paper; there are no jobs to be had for a good while. This may or may not be the case in California.
PTAs generally don't make a whole lot unless you are lucky to land a hospital job, which may be possible since you already have an exercise science background and relevant experience. Again, it will come down to selling yourself in an interview which you could probably nail with your exercise science degree alone. Personally, I would rather pursue a physiotherapy degree over a PTA, especially if you are looking for better job security.
Athletic therapy is only really lucrative if you are providing care to elite athletes. That requires connections and really working your way up in the industry. Outside of that, you'll probably command the same wage as you would with you exercise science degree alone.
I already made my comments about nursing so I won't repeat except to say that it has great versatility and you would likely find a niche for yourself that you love. However, the economy downturn has hit nursing as well and so you will have to put a lot of effort into landing your first job.
I hope that helps you, if even to just give you some food for thought. Hopefully you can get some Californian perspective as well.
Good luck on your journey