For me 3 is the wekeast, and 4 the strongest. To be honest I struggle to remember 3 that well - possibly because the main character felt really generic, and it was superseded in my mind by the excellent P4. I also played the Portable version of P3 which didn't actually involve any walking around outside of dungeons, so maybe that affected my judgement.
Yeah that’s also how I played 3. The more visual novel style did cause it to lose a lot of Persona charm but I still prefer the friends and story to 5’s (so far). The main character was more generic though yeah, good ending though for him/her and one I’d like to see brought back into the overarching story.