I think I'd rank the ones I've played:
Vesperia
Symphonia
Berseria
Graces (f)
Zestiria
Legendia
Xillia
Phantasia
Xillia 2
Dawn of the New World
Really, though, they're more in tiers. I feel like Vesperia is my clear favorite (albeit, it's been a while since I've played it; I bought the remaster, which I need to get around to), and Symphonia to Legendia are all games I really like, so there isn't much difference between them. Xillia is really up-and-down for me, since I like some parts and hate others, and Phantasia is low more on account of its age. Xillia 2 is similar to Xillia, except the dumb parts are even dumber, and Dawn of the New World is similar (except its combat is also bogged down for stupid reasons).
I'm actually just starting a 2nd playthrough of Zestiria, which I haven't touched since it came out, having just watched the anime adaption. Really ****ing bizarre adaption, btw -- do not recommend unless you like flashy fight sequences with little substance, and thought the games really needed a lot more Alisha and Mikleo.
Your opinions are weird. Are Zestiria, Berseria, and Vesperia the only ones you've played? That kind of explains it, but also not really?
Even though I like Vesperia a lot, I do kinda wonder if there isn't some fanboy sentiment behind its reputation, with it being a bought-out XBOX 360 exclusive -- I know it's 90% of the reason I even own that system (worth it!), and it seems like segments of video game fanbases really try to hold up exclusive games. I remember being on the fence about buying a Vita, and it really sounded like Persona 4 Golden could walk on water (probably the most overrated game I've ever played. It's still really good, so to still be overrated just shows how insanely overhyped it was by its fanbase).
Graces F really changes up the battle system, they do away with TP entirely which took some getting used to, but I enjoyed the game. Abyss was released before Vesperia, if you've played Symphonia then the battle system is kind of a mix between Symphonia and Vesperia. As for story, takes a while to get good in my opinion, but that's pretty typical of Tales games. I have nothing good to say about Xillia but a lot of people like it.
I like both battle systems, but I think I prefer the TP-based ones... although it seems that's gone to the wayside, now. Xillia actually might be my favorite combat system overall, but yeah, the game on the whole is dragged down by Milla being, like, the worst character ever, and the whole plot revolves around her. Plus it's basically a deconstruction of your typical Tales plot, which is kind of weird to play through.