So much of Vesperia is broken as long as you're not playing as Yuri.I like the series.
I tend to battle as non-main characters as their battle styles are more fun. I think Regal is the most fun to use, but Judith is pretty fun too.
I like Zestiria and since it takes place after Berseria, you might want to go after that one next.My first Tales game was Tales From The Abyss on the 3DS. Honestly it was one of the best games for the 3DS and ended up spending two weeks on it until I finished it. Went onto Tales of Hearts R which is my favourite, before finally playing Berseria, which was alright but not as good as the rest.
Symphonia and Zestiria are on my list to play but it's finding the time and the agony of choosing which one to play first.