Animation- For most of the show it doesn't look bad. The animated versions of the characters look nice and the line work has a distinct look to it. The 3D models don't look bad either, and they do good job of translating that style into 3D. Unfortunately, it's when they start to move that it shows some issues. Not every scene of the models moving is bad, but there are some noticeably awkward moments when they're running. It's not terrible, but it's hard to overlook.
Voice Acting- I watched the show in English, switching over to Japanese for a handful of scenes. The English Cast was never bad, especially Jin's actor Kaiji Von Tang. He was acting his butt off in some of those scenes... I wish I could say the same for the others. No one was bad, but most of the characters felt lifeless. It just felt like they were there to get a check a lot of the time. Heihachi's actor didn't quite feel like a fit and he took a lot of pauses in his speech. I get that was probably done to match the lip flaps, but it just made his speech feel long and drawn out.
Fights- The fights do feel fanservicey in a good way. They had a nice way of including the hit sparks from the game to convey damage vs. blocks. And we do even get to see Rage Arts/Drives at a point. We even get to see some characters in their stances during their bouts. But I found myself bored with the fights after episode 2. It felt like the impact was just lacking in places and it was hard to gauge a character's sense of damage. Their model gets scuffed up, but I never really felt like they were really hurting each other. Additionally, there's a few fights that we don't get to see. Like I said earlier, they bring in characters from later games to fill out the tournament roster, but aside from leroy we never actually see them fight which makes the whole thing seem pointless.
Overall the series had potential, but it felt hollow. The tone was overly serious and the fights just weren't all that interesting to watch. I felt like Tekken is seen as a serious fighting game, but it's also goofy at times which is what I enjoy most. Without that balance the series came across more like Tekken from the perspective of someone who looked at the roster and watched the series recap from Tekken 6. Again, not a terrible show, but I personally don't recommend it if you're not interested in the series already.
