Vesperia is closer to Symphonia than it is Abyss. It's a bit less charming than Symphonia, but I'm also a bit more jaded on the series at this point.
Symphonia was my second Tales game - having played a translation of Phantasia for the SNES back in the early 2000s. In reality Phantasia and Symphonia, while both wear the Tales trappings, have very little in common.
Vesperia was my fourth Tales game, and it has quite a lot in common with Symphonia and Dawn of the New World.
The funny thing about DotNW is that while I dislike Emil, he and Marta have an interesting dynamic. Something about what was effectively a 2 1/2 member cast (Tenebrae being an unplayable but ever-present character) made the story feel more direct. It makes the game more charming than it has any right to actually be.
For comparison's sake Vesperia has seven party characters (and no hangers on like Tenebrae), and one is a dog...thing. No two of them have a relationship as well developed as the one between Emil and Marta simply because they can't. There are too many characters to pull that off without making the game even longer. In its place you get things like mix-and-match conversations in battle designed to show developing group camaraderie. For example, when one character has a tendency to try to get people to high five her after a victorious fight. If she ever tries that with the dog she crouches down so he can reach, and he simply barks at her and offers her tail. She exclaims, dejectedly, "Your tail!?" The best the game manages with regard to these kinds of relationships is a collective relationship the members develop as they begin to understand each other. Character conversations reflect that as the story progresses, but in the juvenile way one would expect from a Tales title. The most explored personal relationship the main character has is to a person who isn't in the party.
So, despite the amazing tangent I just took this on, you can kind of see where I'm going with this. Vesperia is structured markedly similarly to Symphonia, minus the two-world dynamic. Dawn is similar to both (even piggybacking on Symphonia's story and characters), but had a different feel. Also Dawn doesn't feature an over world. You just select where you want to go and an icon on a map moves there. It's quite jarring for this series, but it is what it is. It does make getting places nice and quick though.
Dawn of the New World gets a bad rap, in part because of the very odd monster raising the game features. It's not well explained, and when you get a chance to "evolve" your monsters, it's not always clear that the change you're going to undertake with them will actually make them a better form. I often ended up devolving by accident, only because I didn't know better. I couldn't, the game didn't tell me otherwise. However, about fifteen or so hours in you begin to add members of the Tales of Symphonia cast to your party. At that point its almost always better to have them in the party then your monster of choice, so the entire monster raising system becomes a secondary thought. The monsters exist to plug the hole where future characters will reside. It's a side-effect of the two member party.
If you enjoy Symphonia you'll like both Dawn of the New World and Vesperia, although I certainly wouldn't play them back to back. That's like 200+ hours worth of tales games, and your brain might implode. I would say go with Dawn first if you're interested in it. Its cheesy, but it has some charms. Vesperia, while not a huge graphical leap from its predecessors, looks so nice in HD it might be hard to go back to the others. Cell shading scales very nicely (obviously), and the vibrant color pallet of a Tales game looks nice in HD.
Also, Dawn of the New World gives me this little line: "Courage is the magic that turns dreams into reality," which pretty much was always followed by me exclaiming, "Shut up, Emil!" They must say that line about 200,000 times in that game.
Emil: Courage is the magic that turns dreams into reality!
Marta: Yeah!
Me: So help me God...ONE MORE TIME and I am not responsible for what I do.