I have two letters from my employer (VP of R&D, and head of R&D) as I'm currently a R&D molecular biologist at a gene therapy company. However, of my faculty letters, I have one science and one non-science. I could get a letter from another professor, but she didn't know me very well, is unenthusiastic and would like for me to write the letter myself. I'm concerned that she would then edit it and make it less 'good.' These are all professors with whom I took classes in undergrad, and I TA'd for one of them, and ran a club with the nonscience prof as a sponsor.
I can certainly spam emails asking for letters from others, but they wouldn't be very strong. Would schools consider my two employer letters in place of a science faculty letter? Both have PhDs, one is a DVM as well, but neither have faculty status anywhere. Would it be better to hold off on submitting while I try to secure another letter?