Good combat system, but poor content and too much tedium.
While the combat system is creative and unique, the developers are often unable for whatever reason to take advantage of it, opting to go for huge amounts of monotonous, boring combat (60-80 hours if you do all the side quests). The game would have been much better with less content of a higher quality and more main story content. Most of the side quests involve fetch quests, repeating previously explored dungeons, or fighting the exact same set of enemies 3-4 times in a row. The dungeons are very simple and mostly linear. Even the main story quests will send you on repeated runs to the same areas. You may think that side quest means optional, but if you avoid the side quests you will end up under leveled and poorly geared/funded for the main story, so they really aren't all that optional, especially on the higher difficulties.
There is an arena but you can't skip any of its 150 fights, even if you far out-level your opponents, which means you have to either visit the arena often during the game or spend an hour or more killing weak low level enemies to get to the high rankings. The highlights of the game (aside from a few bosses/quest enemies) are the optional Danger Zones that show up each Chapter. These encounters are usually fun and challenging with unique enemies and strategies to figure out.
Traveling around the map takes way too long. The developers force the player to run into and out of the Core Lifts for no particular reason, which just ups the tedium when passing through the same elevator for the umpteenth time. If you open access to every hex of a level you can teleport back to your base from that level, which is a great idea, except the game is extremely stingy with handing out hexes. The game doesn't transport your party out of most completed dungeons, either. If you didn't bring someone who can use Escape Hexes, be ready to run all the way back out.
There are 10 levels of difficulty, going up to 5x enemy hit points and 5x damage. 10 levels is too many, especially since you have to unlock them in sequential order. I had trouble justifying one play through with all the tedious travel times and side quests, let alone 10. Furthermore, at a certain stat/gear level the games mechanics can be broken so it doesn't matter what the enemy stats are. Like all traditional RPGs, every bit of difficulty the game throws at you can be mitigated by grinding or hitting retry until you trigger an instant kill or full scratch ability.
Despite what you may have read by poorly skilled gamers, you do not need to grind at all to complete the game on the default difficulty. With that said, the game can be unforgiving if you don't have a decent understanding of the combat system and gun customization. If you're not used to learning and following sets of complex, arbitrary game rules, you may find yourself in over your head.
The post-game is your typical Tri-Ace dungeon of palette-swapped enemy repeats, all with bigger numbers of course. A level 80-90 party with good gear that can walk all over the main story final boss will still find themselves one shot by the big numbers in this dungeon. There are a few unique bosses but they are nothing special because once you've got the stats and gear to reach them, they will be trivial to defeat. Like most post-game RPG dungeons, it's more about making your numbers bigger and/or breaking game mechanics than any increased strategy or complexity.
The weapon customization is fun to figure out, although there isn't much variety once you realize that Charge Acceleration is the best stat. Piecing together a Frankensteinian monster of a gun with 7+ barrels and scopes hanging off the ammo clip can be entertaining. The customization interface could use a lot of improvement, though. There should be a customization preview feature that lets you experiment with as many parts as you want - this would be good for learning how the parts go together and for optimizing your desired setup.
As creative as the combat system is, it's clearly rough around the edges. This is a common problem with RPGs and developers who keep inventing new systems with new unpolished and untested gimmicks instead of improving on a previous formula. Handguns feel useless for anything besides cashing in on scratch damage and gauge breaking/stunning. I would have liked to see a better balance between direct damage and scratch damage, so it isn't just 'scratch and cash in with one hit'. There is often unnecessary delay after enemies have finished attacking, up to 1-2 seconds with the game sitting there and nothing happening. Enemy AI is incredibly dumb around any kind of elevation and will frequently fire into walls and ramps, and completely miss many of its attacks.
Switching targets during a Hero Action is clunky and hard to control. After killing a target during a HA, the computer likes to select the farthest target from your character instead of the closest, which is poor design. The developers should have added the ability to set 4 target markers on enemies that you could switch between with the 4 shoulder buttons during a Hero Action.
Collision detection is flaky and makes the combat feel clunky and uncertain. Some large enemies (Goliaths) have hit boxes far larger than their actual model size, resulting in frequent bumping into thin air near them. It's also possible to bump into small elevation snags like ramps, or bump into thin air near terrain corners, even when jumping. To add insult to injury, bumping into an obstacle (fairly or unfairly) will result in your action being ruined and time will pass while your character stands back up, giving enemies plenty of time to charge up attacks.
There are some real time elements in the combat system that give it a slightly higher skill cap. The Target Airborne bonus ring requires good timing to constantly hit. Sometimes you can outrun enemy attacks or hit them while they are recovering from an attack or knockdown, which requires coordination and speed. Few players will be able to claim that they've completely mastered the combat system and know every little trick in the game, or how to best deal with every enemy type.
The graphics are adequate if bland, although the enemy design is good. The music intensifies with extra instruments once you start a Hero or Tri-Action, which lends some intensity to the combat. Most of the music is good and there is a lot of variety, you won't be stuck listening to the same music very often. If you like playing with barbies, there are lots of clothing options for your characters.
For 90-95% of the game your own characters are stuck toiling over petty issues or doing mercenary work for eccentric nobles. Even after you learn all of your characters back stories, they continue doing pointless mercenary work. Cut scenes each chapter slowly fill in the back story and plot involving Basel and Zenith. It's kind of sad when the most compelling part of the story is acted out almost entirely by NPCs. Not that the main plot is much more than cryptic techno-babble and the ever popular 'mysterious secret experiments' plot device. Your main characters only get involved in the main story in Chapter 15 out of 16, which is the last 5-10% of the game. And then there's the Christmas quest. Good lord, what were they thinking? You can't lose and it's an annoying waste of time.
As much as I really wanted to love this game for its fun, slightly unpolished combat system, the game continued to disappoint me with its tedium and lots of poor repetitive content instead of a smaller amount of quality content. Hopefully a sequel will rectify the wasted potential this game had.