The BSN idea is good too. Just don't get sucked in to a really expensive program. Here are some caveats about doing a fast track BSN to help you get into PA school. First, they can be very competetive in their own right, and if you aren't well positioned in your grades to get into PA school, you might not be a sure thing to get into an accelerated BSN program either, unless you go for one of the more expensive for profit/private school programs (they are out there, and they can cost you considerably). And if you really want to be a PA, it doesn't make sense to go the nursing route... I don't personally know a single nurse out there going for PA. They exist, but most nurses end up shooting for NP school... typically they are a lot cheaper, and we like to work while we do school (in pa school you pretty much can't).
I wouldn't want to take my eye off the ball and retool to get into nursing school unless it involves no further effort to get in to an accelerated BSN. I'm kind of an example of that, but in a good way for me (overall it saved me at least a couple hundred thousand dollars vs going to PA school). I was deciding what to do following a rejection letter from the only PA program I wanted to get into. Then my acceptance letter came in from my nursing school. I could have reapplied to PA school and gotten in the next year, but I did nursing instead. I was lucky because my best grades I got were also in nursing prereqs, so I coasted in to RN school without having to take any more prereqs or improve my grades.
The scenario with the meandering path that I wouldn't want to do is to decide to do an accelerated BSN, then have to take a couple classes as prereqs to get in, then get in to a really expensive $80k BSN program, then get done and get into a $100k PA program, then pile all that on whatever student debt you already have, and then start life as a PA making the typical starting wage of $93k per year (incidentally many nurses I know make that much working less than PAs and NPs).
To sum up... If you do an accelerated BSN, it should be a cheap one you can just walk into as is. And if you do a BSN, you might as well just do NP at that stage. NP programs are typically $20-40k, and you can work as a nurse while you do it. I certainly would do the BSN vs an MPH or any other post bac out there with the exception of lab science. With lab science you can really boost your science gpa because it's a bunch of fairly straight forward coursework that a biology major can do well in. And with lab science or a BSN there is a real job waiting for you once you are done with school. My first two years as an RN I made about $80k per year working 3 days a week and a little bit of overtime. As a med tech before that I was pulling in about $70k, which isn't bad in my state. It's not PA money, but it didn't come with PA school price tag either.
With a 3.0 gpa and a lower science GPA, I really would suggest either of those two approaches because you have an uphill climb If you are like I was, you don't want to miss out on life along the way. I've been gainfully employed all along my path to becoming a provider, which has been nice. I was glad I killed two birds with one stone by getting a degree that helped me work while I also knocked out coursework that got me closer to PA or NP school. After getting my biology degree, I wasn't in the mood to double down on something that didn't have a direct route to a decent paying job. An MPH or one of those lame masters programs that some schools offer to professional school rejects are money pits. I wouldn't double down.