I mean Tera's combat is better than most free to play MMOs, but for me, it still has that MMO feel at the end. It's not terrible, but you have a game like Phantasy Star Online that gives you actual controlled action. Difference being one is open world and the other isn't, but PSO2 has some nice sized levels. The combat is Tera's shining point, but for someone who's played a lot of MMOs over the years, it wasn't enough to keep me playing it past the first month and even when I tried it months later, it wasn't drawing enough for me.
As far as the last bit, I find Japanese MMOs actually feel like I'm playing a 'game' and not a 'mmo'. MMO's usually have watered down combat systems compared to console/handheld games, like there are a few to the exception, but FFXI, Phantasy Star Online, Phantasy Star Online 2 and FFXIV to me feel like what I described before. I feel like I'm getting a single player game but it's also a MMO in terms of mechanics. Even Phantasy Star Universe, although, I didn't care for that one too much.
My issue with most western MMOs is usually I don't enjoy the combat in them. I did enjoy City of Villains, but that's been about the only western MMO I've enjoyed.