I’m also interested to hear everyone else’s thoughts on this 
I think you already know my current thoughts, but based on feedback and looking at reviews, I’ve come to the conclusion that there needs to be a degree of railroading happening for an overall happy audience.
I’m guessing a lot of people only read through once (or leave a review after their first play through and then don’t change it later) and will leave lots of “way too short!” 1-2* reviews since the more your story significantly branches, the lower the overall word count will be for each story line. Some reviewers don’t understand that the total word count per story listed in the blurb is not the story count (I’ve seen it a few times where there have been complaints that the story they read was “no where near 100,000 words” etc.) but I think they’re probably in the minority. In saying that if it says it’s 100,000 words and the story branches so much that many storylines are under 20,000 it will seem unexpectedly short based on expectations of length, and create unhappiness.
Iron Destinies does sign post different storylines quite well but then has “the branches are railroaded” complaint. (I’ve only read it once so that’s not my opinion, but if that actually is what it does, I’d imagine it was done to stop the word count spiralling out of control). Storylines that are too railroaded will still get complaints as well, but it seems to be regarded as a lesser evil than lower than ave words per play through by most reviews I’ve seen and will generally get judged less harshly as long as the story itself is well written.
So short version I don’t think you’ll ever keep everyone happy. Some people like lots of replayablity, some people just want 1-2 play throughs of an interactive story. From what I’ve seen from reviews vs stories, the ones that often do best have a strong core story line with lots of flavour text influenced by stats and choices so that playthroughs sound different, and “side quests” that branch away from the story then rejoin it somewhere so you can get some replayability out of it. Ideally have few well sign posted diverging branches in the ending sections, especially if it’s not going to be series, to confirm the “multiple choice” nature of the book. (Think stories like metahuman which I think did this quite well). Otherwise branch, but have a large overall word count with a few very well signed separate branches each with strong finished story lines. Those are my current thoughts anyway and may be subject to change