Simple Days for me feels completely differently, way more linear, I wouldn't even call it a proper sandbox. Also way faster pacing.
Straitened Times (again in my feels only) indeed is pretty similar in many aspects but has more interdependencies between the characters (e. g. to get ahead with, or even a head by, the motel manager, you need to improve your relations with the police officer, which in turn needs progress with the lawyer to be unlocked, etc.). But a good suggestion for people who like LSSB certainly.
Milfy City is abandoned, as you say, and has less content. Could have gone similar to this, includes mini games (which I thought were actually okay) but has a different tone.
Summertime Saga doesn't have that little content IMO, but a slower update schedule. Art is drawn 2D, even if more comic like. A possibly good suggestion as well. It even sometimes has events not triggering properly and having to restart/reload an old save, if that is your kink
Don't know Masters of Raana.
Another game that comes to my mind, that also has free time roam (i. e. not 3-5 phases a day but actual hours and you take a certain amount but can roam at night if your energy holds like here - or in Straitened Times) would be Man of the House. Fewer LIs. Only one pregnancy option though and only in the ending, and only one harem option (which is a bonus after you 100%ed the game), also again interdependencies - you need to go pretty far with the landlady to unlock the superhero as dateable, also the roommates block the paths of their BFFs.
But yeah, looking for sandboxes is probably the best. See whether you like the graphics, read a couple of useful reviews (I know, they are few and far between) to see what people like and dislike about it. I personally could add Photo Hunt (silly stats system though) or Love of Magic (if you though coordinating your girls here is hard, you ain't seen nothing yet), maybe even Hail Dicktator (BDSM heavy though, and less "normal life"), but in the end it will be individual what precisely turns people on here and is different or similar elsewhere.