ROTS is literally the only one that adds anything to the OT story at all. It’s the only one that actually could really even be called a prequel in that it is the only one that has events that actually lead into the events of the original directly and tie into the main story of the original. It’s the only one that fleshes out the characters of the original (Vader particularly) in a significant way and the only one that changes how you see some of the events in the originals for the better (mostly). I’ve said it before, but I still think the idea that Anakin turned to the dark side to save his child and then turned back for the same reason was the best idea Lucas had in the prequels and it’s what makes machete order work. It adds a strong link between 3 and 6 that holds up well when viewed back to back.
And yeah that’s great, Episode 1 had a few more miniatures and was shot on film. Episode 3 still even looks better because at least the CGI, more of it though there may be, hasn’t dated quite as much as Episode 1’s CGI has. And the score? The score is great in all three, that’s not an advantage to TPM specifically. And Qui-Gon is a memorable character? Really? Qui-Gon never needed to exist. It should have just been Obi-Wan from the start. I love Liam Neeson but the character is pointless. Watto is memorable for all the wrong reasons as yet another racist cartoon alien with a dumb accent.