First things first. Forget the Rocksteady Batman Games. Do it. Well try to. Because if you are going into this game thinking it's going to be anything like the Rocksteady Arkham games you will be infinitely disappointed. The movement is tricky (a little too fluid), the combat is stiff and repetitive, and the writing and voice acting is laughable. But I love this game and absolutely recommend it to any fan of superheroes, or RPG games. And here is why.
Even if the gameplay gets repetitive, the constant returns to your home base are rewarding because of all the custom stuff you can play with. You can customize the color of your Batcycle, the color and look of EACH suit in the game, and a decent skill tree for each character. And the game levels up the other three Knights based on your highest, so you can customize them whenever you want. The real success here is the customization for suits. There are a LOT of suits available for each character, and they are easy to unlock. You can even customize the suit itself, changing the cowl type, arms, feet, and chest. The customization is what Marvel's Avengers promised but never gave us (you'll be seeing that line a lot here). The costumes stay during cutscenes, so it's a pretty cool system that makes you feel like you actually are the character, almost like they are taking a different suit out each (k)night for patrol.
2) The Boss Fights
A LOT of the combat in Gotham Knights is repetitive, especially against the standard goon. But an area the game does really well in is the Boss Battles against some of Batman's Rogues Gallery. As of this writing I've fought Clayface, Harley Quinn, and Mr. Freeze, and each of those fights has a LOT more mechanics and thought put into it than Marvels Avengers. Which isn't saying much, all three fights have good mechanics, but nothing original. But those three fights alone outshine any boss fight in Avengers, so I look forward to whoever else is in the story, plus any DLC boss fights they decide to add before Warner Brothers messes this game up. Each fight required coordination between you and your partner, so it really does make the coop part of this game shine.
3) The Co-Op
Gotham Knights confused us all when they announced the game would have two player co-op. A big part of the appeal was being able to play with friends as members of the bat-family, but you can only do that in a 4 Player "Raid" coming relatively soon. The main story is two player co-op, which is a baffling choice until you see how the game can barely handle having two players on the screen. The two player experience is solid, giving the players freedom to help save Gotham however they want. You can stop a bank robbery while your partner goes and interrogates someone three blocks away. There are also team up take downs (shaking my head at Avengers) that you can utilize frequently, and a lot of the abilities build off of each other pretty well. For example my Nightwing keeps the crowd busy while my partner Red Hood shoots them from afar. The stealth co-op is also a highlight, as you and your partner can coordinate to take down a room pretty easily without being spotted. That is unless you click one of the many confusing inputs and fire your weapon randomly instead of doing a takedown. Overall the co-op might not be award winning, but it's a fun journey to take with a friend. Hopefully Gotham Knights releases more four player based content so the game can be enjoyed fully. And with Talia a main player in the story it would be awesome to see Damian get introduced as a fifth player option.
Summary: Gotham Knights is a fun co-op experience, but is weighed down by horrible writing, repetitive combat, and clunky mechanics (which an update yesterday actually fixed some of). If you enjoy the Batman mythos (as everyone should), you will enjoy this game. If you expect this to be an award winning Rocksteady like Arkham game, you will be immensely disappointed. Go in with low expectations, grab a friend, have fun, and you'll enjoy this like you would watching a bad movie in a theater with friends. I know it's not a Games as a Service game, but with the right DLC this game could significantly improve, so here's hoping!