SS is a better game ? Debatable. By every metric ? Hell no.
In in SU if you want the porn scenes it's not really hard(except if you don't use cheats, in that case yeah the game is pretty terrible). Yeah there is a gacha component where once a while you have to skip a day, how time consuming it is.
Nothing like a Point & Click where you're lost if you don't pay attention, where you have to always go to bed, wait for a precise day,... Sure it's that sort of game, but the time spend before you can get one porn scene is so absurd in SS.
So the art ? Nop.
The content ? Maybe, didn't bothered to finish it after I was lost because I didn't played for a while. But from what I've seen in terms of sex content, not really. (I mean sure it's nice and all to have great backgrounds to visit and all, but a lot of porn games forgets they are... porn games. If it was just for the diversity Innocent Witches would be the best porn game).
The story? It's a porn game, who cares ?(and tbh SS has not what I would call a good plot)
I mean sure, there is some points where I think I'm not really objective, but SS isn't that much of a great game, and SU is a good porn game, it's just the developer who is a disaster with communication.