Speaking as someone who had played read quite a bit of both CYOA-style gamebooks, without any stats and Fighting Fantasy, Lone Wolf and other gamebooks where stats and/or abilities for your character where an important part of the book: I started by playing/reading CYOA-style gamebooks and enjoyed them a lot then, but after having played/read Fighting Fantasy, Lone Wolf and other series with stats for your character, playing/reading CYOA started feeling lackluster in comparison.
I think this had to do with a couple of things. Firstly, without no stats and abilities for the characters, the characters felt more vague and without a real core, there was less to really grab unto to give me a sense of what the character was like than in Lone Wolf, Fighting Fantasy and other gamebooks where the characters had stats and/or abilities. Of course, if interactive stories that follows a more anything-goes approach, where you can jump from one storyline to the next, like you do in some interactive stories, this can still feel entertaining in its own way. But if you want a story where the MC interacts with the rest of the world and the rest of the cast in a way that both makes them feel like a proper person, who are in a kind of relationship to the world and the other characters in the story, and makes you truly care about them, it’s harder where the MC has no really discernible qualities and nothing really to hold on to when it comes to defining how the MC is, at least unless you fully self-insert. But if the MC in question has stats and/or abilities or something else that can work a bit like stats, ithis can work as something for the reader/player to grab onto to give them at least a bit more sense of who the MC is. So I think it’s important to keep in mind that a MC without any stats can easily feel too vague and without a clear character to a player/reader,at least unless you put something else in place that serves the same purpose that stats can serve.
The second reason, I think, for why the CYOA-style gamebooks felt a bit lackluster after having played/read gamebooks with stats for a while, was that I missed having cool abilities that could affect what happened and for stats that could do the same and after at that point also having played quite a bit of tabletop rpg games, I think I also missed having character sheets for the MC, with stats and other stuff. And that’s another thing to keep in mind, although we’re probably not anywhere near as vocal about it as those who dislike it or even hate it, there’s plenty of players/readers of COGs and HGs who actually enjoy stats and similar gamey aspects, at least as long as they’re done well. This might be a weird be just a weird hobby of mine that is shared by no one else, but I have to admit I do really enjoy just creating rpg characters and creating adventuring scenarioes and imagining them gaining experience and levels. I got at least some of the same kind of thrill in COG/HG stand alones or series, where I can gradually “build” their stats from mostly comparatively modest to the point where a lot of those stats are really powerful. And if all stats are taken away, with nothing to take their place, I lose all of that. Sure I can still enjoy a COG or HG there’s not much opportunity to “build” the MC’s stats, if the story and/or ROs are really enjoyable, but the bar for what counts as enjoyable enough will then be much higher than what is the case with the the HGs and COGs that gives me the opportunity for the kind of character building I like. And so I think it’s important to keep in mind that there’s probably also a fair amount of people who, like me, actually enjoy stats and stat tests, and who would likely feel that if a HG was without any stat tests and stat checks, it would be poorer for it.
I’m not saying that I don’t see any issues with the way stats are sometimes implemented. I vastly prefer “stand alone” stats to opposed stats and stats to do with abilities, attributes and skills to personality stats. You can’t build opposed stats the way you can build stand alone stats, and the way that opposed personality stats are used in a COG or HG that uses stat checks for those stats, encourages you as a player/reader to try to tactically choose your MC’s personality stats instead of roleplaying a particular personality and so can, in a way takes away some of the personality of your MC. So there are obviously dangers of the misuse and overuse of certain kinds of stats, as well.
I do however think that stats, as long as you don’t focuse or at least focus to much on opposed stats, particularly opposed personality stats, both makes it easier to get a clear picture, so to speak, of your character, and is a source of enjoyment for those of us who likes to build our MCs or in other ways enjoy gamey aspects and features in COGs and HGs. So if you plan on leaving them out, I think it’s also important to ensure that you have other features in place that can serve the same purposes or find other ways you can make up for the lack of stats, ways that would also please those who like/enjoy stats.