This comment got long–sorry.
For interior bells and whistles, I’m an purist in that I don’t want sounds (to me, that’s some other sort of beast, not what I’m after). I don’t think they make a game bad, just not for me. A game that’s dependent on images–seeing clues, etc.–would be interesting. If there’s art, I wouldn’t want it to be distracting from the text or so large that you have to scroll around it or so large that the author skimps on the words. If it doesn’t make me have to do extra work to see the story, then it shouldn’t affect whether or not I’d want to buy the game. I haven’t seen art and IF integrated well, but that’s on me, because I tend to avoid those games. I should expand my horizons, or even try making a game like that myself.
In a printed book, I love having lots of art.
Cover art: I’ll admit that I’m attracted to books/games with well-designed cover art. It gives me confidence that the writer or publisher has a good eye and good judgement, or that they went to someone with an eye for design so maybe a lot of thought went into the rest of the package. There’s an element of “ooo, sparkly, must have.” The right cover puts me in the mood for the game. I’d also enjoy seeing art at each significant chapter break.
Also, the more games there are to choose from, the more helpful it is to have something that’ll get people to take a look at yours, whether it’s a great title or eye-grabbing cover art.
That’s what gets me to pick up something. But after that…it doesn’t really matter. And if, say, something had what I’d consider the worstest art ever, but someone told me it’s a great game, I’d read it anyway.
The image I’m using for my WIP is one I love because it says “step back through time” to me, but maybe the game will end up with something entirely different that’s more broadly appealing and exciting