I loved Graces f. Cheesy story and friendship themes aside, the game was awesome. Arguably the best battle system ever.
Symphonia > Abyss > Graces f > Xillia (never finished it) >>>>>>>> Symphonia 2
Just heard that Berseria has the darkest story/characters in the series. Excited! Only bought this because of the price and because it's Tales, but I'm legit stoked about it now.
Oh yay! I think you'll like Berseria. Berseria uses a similar dodge mechanic and resource management (although I still give the edge to the CC system of Graces). It's definitely the "darkest" Tales story that I've played, but it's a fun ride and I liked all of the characters.
If you end up enjoying Berseria, you may want to try Zestiria because it's set in the same world in the future, and several characters from Berseria show up. Zestiria overall isn't the greatest game, and many people don't finish it, but I think it's worth it for all the references.