Lets start with the generals-- Art is respectable enough, though I'm not a particular fan of the style. Audio checks out okay. UI works out well enough, though I had some responsiveness issues... might be just me. Thankfully, there's a button to highlight objects you can click on so you won't be pixel hunting for containers. (Not everything-- I noticed that people and flavor text-only items didn't get highlighted.) Combat is hex-grid AP-style, so... Fallout.
And some of the flaws. It's entirely autosave, so you I don't think you can have two concurrent games with different characters going. I'm not sure if it's a bug or not, but you can get an evidently unremovable debuff that makes everything blue, fuzzy, lets you see imaginary (or are they? Hard to tell in Arkham.) monsters, and superficially screws with your dialogues (no mechanical change as far as I can tell, just some RP fun). Because making everything fuzzy is fun.
Sanity seems to mostly act as an alternative life bar... low sanity can also cause some problems in combat, though I couldn't tell exactly what the effect I got did. It also feels really slow... even when your character is running, it feels like they're ambling about. Combat feels pretty clompy as well.
There's an interesting touch in dialogue-- during character creation, you have to pick a motivation... and dialogue options that support your motivation will restore your sanity. For instance, I picked Materialism, so asking for extra rewards when finishing a quest helps me out. I haven't found a way to change it in-game yet, so good luck with RP that shows your character changing over time.
Despite all this, I still feel kind of detached. In Darkest Dungeon, I found myself quite attached to my characters, even if they were quite literally Random Paladin G. Over here, they're unique characters and I find I'm just not that interested in their plight. Or anybody's really.