Nobody probably cares about my opinions, but I feel like writing out what I think about the series and what the pros and cons of each game are to try to help me figure out which game I like best.
Asylum
+ Best interior level design
+ Scarecrow segments are still great
- Really basic combat that's hard to go back to
- Same with stealth
- Same with traversal; unrefined glide with no divebomb
- No open world to explore; Arkham Asylum's "hub" is really boring
- Riddler trophies have no puzzles attached to them; they're pretty much just a matter of, "Do you have the key to collect this trophy yet?"
- No sidequests besides the Riddler trophies
- Killer Croc completely ruins the pacing of the game; I've ended multiple playthroughs at his part just because I hate it so much
City
+ Decent boss battles, between Freeze, Ra's, and Clayface
+ The most memorable open world; large enough for it to be fun to glide around in, but small enough to remember where things are
- Obnoxious number of Riddler trophies... but at least many of them have some sort of puzzle to collect them
- Guys with guns make exploring in the post-game a pain
~ I'm not really sure what else to say about City. It's no longer really the best at anything, but it doesn't have any glaring flaws either.
Origins
+ Arguably the best boss battles, between Deathstroke, Copperhead, Firefly, and Bane
+ The detective stuff where you rewound the crime scene to find clues was neat
- Easily the buggiest and least polished game in the series
- Guys with guns make exploring in the post-game a pain
- Enigma data packs don't really have puzzles attached to them or anything; definitely the least interesting Riddler sidequest
- Probably the least interesting sidequests outside of Asylum
- Locked vital upgrades like Critical Strikes and Disarm and Destroy behind sidequests that didn't come until later in the game
- The upgrade system locked upgrades I wanted behind upgrades I didn't want for no real reason
Knight
+ The best combat so far, with better super gadgets and nice additions like the Critical Beatdown
+ The best stealth so far, especially with the Fear Multi-Takedown
+ Traversal is more fun than ever between the Batmobile, the super eject, and the super duper grapnel boost
+ The Batmobile can be fun
+ The best puzzles in the series
+ Some of the best sidequests in the series
+ A more reasonable number of Riddler trophies than City, and many of them are hidden behind decent puzzles or challenges
+ No goddamn respawning rooftop snipers to deal with in the postgame
- While the Batmobile can be fun, it can also be annoying, and there's definitely too much of it
- Not enough interior areas
- Disappointing endings to most sidequests
- Almost complete lack of proper boss battles
- Lack of a proper challenge mode
- Not enough upgrade points to fully upgrade everything with one playthrough
So with all that written out... I'm still not sure what to think. Knight has the most positives, but also a bunch of negatives. City doesn't have many negatives, but also doesn't have many positives. Hmm... I suppose if you'd asked me before I wrote all this out, I'd have said City was my favorite. But looking at this, I feel like I have to say Knight is my favorite. It does enough things best to make up for the things that were disappointing.
Asylum
+ Best interior level design
+ Scarecrow segments are still great
- Really basic combat that's hard to go back to
- Same with stealth
- Same with traversal; unrefined glide with no divebomb
- No open world to explore; Arkham Asylum's "hub" is really boring
- Riddler trophies have no puzzles attached to them; they're pretty much just a matter of, "Do you have the key to collect this trophy yet?"
- No sidequests besides the Riddler trophies
- Killer Croc completely ruins the pacing of the game; I've ended multiple playthroughs at his part just because I hate it so much
City
+ Decent boss battles, between Freeze, Ra's, and Clayface
+ The most memorable open world; large enough for it to be fun to glide around in, but small enough to remember where things are
- Obnoxious number of Riddler trophies... but at least many of them have some sort of puzzle to collect them
- Guys with guns make exploring in the post-game a pain
~ I'm not really sure what else to say about City. It's no longer really the best at anything, but it doesn't have any glaring flaws either.
Origins
+ Arguably the best boss battles, between Deathstroke, Copperhead, Firefly, and Bane
+ The detective stuff where you rewound the crime scene to find clues was neat
- Easily the buggiest and least polished game in the series
- Guys with guns make exploring in the post-game a pain
- Enigma data packs don't really have puzzles attached to them or anything; definitely the least interesting Riddler sidequest
- Probably the least interesting sidequests outside of Asylum
- Locked vital upgrades like Critical Strikes and Disarm and Destroy behind sidequests that didn't come until later in the game
- The upgrade system locked upgrades I wanted behind upgrades I didn't want for no real reason
Knight
+ The best combat so far, with better super gadgets and nice additions like the Critical Beatdown
+ The best stealth so far, especially with the Fear Multi-Takedown
+ Traversal is more fun than ever between the Batmobile, the super eject, and the super duper grapnel boost
+ The Batmobile can be fun
+ The best puzzles in the series
+ Some of the best sidequests in the series
+ A more reasonable number of Riddler trophies than City, and many of them are hidden behind decent puzzles or challenges
+ No goddamn respawning rooftop snipers to deal with in the postgame
- While the Batmobile can be fun, it can also be annoying, and there's definitely too much of it
- Not enough interior areas
- Disappointing endings to most sidequests
- Almost complete lack of proper boss battles
- Lack of a proper challenge mode
- Not enough upgrade points to fully upgrade everything with one playthrough
So with all that written out... I'm still not sure what to think. Knight has the most positives, but also a bunch of negatives. City doesn't have many negatives, but also doesn't have many positives. Hmm... I suppose if you'd asked me before I wrote all this out, I'd have said City was my favorite. But looking at this, I feel like I have to say Knight is my favorite. It does enough things best to make up for the things that were disappointing.