I don’t know where I saw this (Reddit?), but the following is a PERFECT description of Sunless Sea and its main problem: It has the gameplay of a rogue-like (play a bit, die, replay earlier bits, get a bit further, die, repeat) and the story structure of a graphic novel (read once).
That’s… a bit of a problem, especially because gameplay-wise Sunless isn’t awesome. The ship combat is actually terrible (sit behind a dumb AI ship, shoot, win. Shoot creature, it ramps you, repeat until you or it dies), and the collecting/trading aspect is somewhat poor (there isn’t a ‘quest tracker’ so you either sail around somewhat blind, or take a ton of notes on paper). Then you have the fact that, for long stretches of time, especially further into the game, you’re just sailing with nothing to do and nothing happening other than occasionally dodging a ship/creature. Double ‘fun’ when your ship is slow due to lack of crew, or you go from a faster ship back to the starter ship/engine.
The writing and setting are very good, as is the art/sound presenting everything. The game captures the madness aspect really well, without going too far down the pure confusion or nonsense side. This is what will make you want to keep playing. To open up the next step in a quest, or finally open up a certain area of an island because you now have the required item.
However even this is spoiled somewhat by the gameplay. Multiple times I finished a great quest lore-wise only to be rewarded with less ‘stuff’ than it took to complete the quest. That’s a huge fun-drain, and tarnishes the writing and story progression. Also the game only half-works in terms of repetition. The location of certain islands will change, but others won’t, and enemy spawn locations never change, nor do quest objectives or results.
The result is that the more you play, and the more you die and repeat the early game, the more you are skipping text you have already read, leaving you only with the gameplay. And again, that gameplay isn’t great. Grinding out stats or money in Sunless is a really poor use of your gaming time, and because of the somewhat random nature of the game, a death and restart is somewhat common (to be fair, its not as random as most rogue-likes, and on the 3rd or 4th captain I was basically able to stay alive if I didn’t push things. However not pushing means you sail back to port more, which just increases the bad parts that much more).
What is funny/tragic about the whole thing is the game pushes you not to disable the ‘one save only’ system, but if there was ever a game that should be played with the reload option, its Sunless. There are enough stories and islands to visit here to get your money’s worth even with just one captain, so I highly recommend you turn off the one-save system and reload whenever you die.
All of that said, I’d still recommend Sunless, especially at a discounted price. It’s flawed in some pretty major ways, but even despite those flaws the setting and stories, as well as the sense of discovery as you sail around, are worth picking it up and spending a weekend/week with. Don’t expect greatness, but do expect to be entertained.
Hardcore Casual 
Fair overview. There are smarter enemies out there (the Khanate boats with rear-mounted guns come to mind) but one does not play this game for any kind of dexterity challenge. It comes down to digging the atmosphere and its particular flavour of rogue-like strategising – supplies, order of missions, route optimisation, etc. – or not.
With regard to anemic quest rewards, there is also the matter of the victory conditions. To achieve all of them save for the wealth ambition, one needs to have exhausted a bunch of the plotlines, and so it makes sense to pursue them even at a strict loss in resources. This kind of inflection point isn’t really unheard of in rogue-likes, particularly toward a game’s end.
The outcomes of more complex quests (e.g. the Sisters of Hunter’s Keep, the deviless plot, etc.) can change a fair bit between playthroughs, but it is definitely true that the writing is the game’s strongest point, which does affect replayability.
Im kinda scared The Banner Saga http://store.steampowered.com/app/237990/ will be like that this first play through is super fun but if is the same things every time prob only play twice if its not you should check this game out I really enjoy the hand drawn style of animation
Sunless Sea was the final confirmation for me that I do not care for roguelike games. I own a number of them and I always get annoyed with them and quit long before I finish them. I just don’t take to the idea of replaying the same stuff over and over again with “randomness” as a substitute for variation. I went back and forth on buying Sunless Sea for about a week before deciding to get it due to the great reviews and the aesthetic and Lovecraftian atmosphere. I played it for about 4 hours before I just couldn’t deal with the repetition anymore, and as you say, the core gameplay just doesn’t make up for it. The premise of roguelikes, incremental progress on repeated playthroughs of same-y content with a RNG dictating much of how far you get, just doesn’t do it for me.
It’s why I won’t be buying Darkest Dungeon, despite it appearing very appealing in terms of gameplay and look and feel.
DD has less repeating in a lot of rogue-likes for a few reasons. First is that who you take into a dungeon changes a lot of the gameplay, and since what heroes you get is random, plus what heroes you can use on any specific run isn’t set in stone (who isn’t being treated for something in town), that mixes things up nicely. On top of that, the core gameplay is fights and moving to the next room, and assuming you enjoy that, it doesn’t really feel like repeating old content, but rather just consuming more of the ‘core’ of the game.
Interesting. Might have to use the Steam 2-hour trial method to see if I like it. Think that’s enough time to make a decent assessment?
I’d think so, that’s enough time to run a few dungeons at least and get a flavor for the game, yes. You might still be a bit confused about a lot of mechanics, but I’d say you will know if its something you want to buy or not.