1. I worked in a research lab in undergrad (graduated in 2010) and my PI is still willing to write me a LOR. I believe she will write me a pretty good letter. She wrote one for the last app cycle, and I'm assuming she would be looked at as more of an academic reference, but since I last worked for her 3-4 years ago, I feel that it's a bit out of date...
2. I worked as a Health Science teacher for 2 years in an urban area. It was a challenging job and as a new teacher, I was assigned a mentor by the building principal, and he happened to be the lead teacher for the science department. He was amazing! H received $100,000 grant for our department for having his students sequence a gene of a sunflower, we developed a co-taught pharmacology unit together for our seniors, it was overall a great experience. He actually was in medical school for 2 years before leaving (by choice) and pursuing teaching. He offered to write a letter for me as we became pretty close over those 2 years; he didn't want me to leave the district. I'm sure he could attest to my abilities. I really want to ask him, but I'm thinking that many PA schools won't see it as a good reference because he was technically a "colleague" and is just a "teacher".
My other letters will come from my charge nurse on my floor (she's great and see's me work with patients almost every time I work if she's charge) and a surgery PA I've shadowed a couple of times- really supportive and gives good guidance for application stuff.
What should I do?