Most of these are bound to a language: choose a language first (and my answer to that question is "whichever one you're happiest working in and can get the job

Most of these are bound to a language: choose a language first (and my answer to that question is "whichever one you're happiest working in and can get the job done"), then figure out which backend to use. You can fret over the framework more after you've already built something that works.