I finally finished this after having it in my backlog for over a year. Played through all four paths on Hard/Classic, clocked in over 150 hours (and probably put in much more with the number of times I reset...)
I have a love/hate relationship with the RNG mechanics for leveling in the series. I absolutely LOATHE getting a bad roll on a level-up, to the point where I will reset if too many of my characters get RNG-screwed, yet I always get a thrill when a characters gets an overly generous roll (e.g. increases in 7+ stats) and having my characters OHKO enemies by end-game. I really wish they just standardized the level-ups and left the RNG mechanics to hits and critical strikes, but they've stuck with the formula for so long I'm not holding my breath. I will say that the Divine Pulse mechanic was a nice way of managing and undoing bad RNG rolls in the shorter maps/auxiliary battles.
Plot-wise, I appreciated that each path gave a different perspective, but think it's a bit unfair that you don't get close to the "full story" unless you play through all paths, with some paths feeling very short-changed. I played through Blue Lions first and at the end I thought "wait, that was it? What about all those unresolved plot threads?" Black Eagle/Crimson Flower was probably my favorite path, but it felt way too short and didn't really give me a chance to develop my team fully.
I liked the additional mechanics you can use to increase support (I think I was able to get almost all characters to max support levels with one another by the end), and that it allowed you to see more character interactions, but on the other hand it did seem to diminish the "meaning" of support levels, especially with the seemingly random way characters get paired with one another in the end.
I think Path of Radiance is still my favorite in the series, maybe for nostalgia reasons, but this is probably a close second, and I did appreciate the various new mechanics/QoL improvements introduced.