Most of these aren't exactly hidden, but they're also mostly not on Itch, so maybe they'll count?
Summertime Saga - Hand-drawn sandbox. Decent story, fun characters, appealing art style. They had to do a full rebuild like Ripples did, and there's...debate as to if the rebuild will ever be finished, but what's there is still a full story and bigger than many other games out there.
Being a Dik - 3D visual novel like Ripples, with short moments of exploration. Emphasis on writing and humor. Probably the #1 AVN of the last few years, it just tells a really good story. The characters have depth and their own voices - I don't mean voice acting, but if you just saw a quote, you'd know exactly who said it. Nine (long) chapters are out, with another likely coming in September. It will engage most of your emotions. Highly recommended.
Artemis - A newer entry. Extremely polished, with great music, models, and environments. Same style of AVN as BaD, but with a twenty-minutes-into-the-future science fiction storyline, which might appeal to you more. Slick writing. The characters aren't as well realized as BaD, but it's early yet.
I'd also second the rec of Once in a Lifetime.