It's a borderline miracle when one manages to get made that's actually worthwhile in that regard, like Sengoku Rance. Agarest was a complete slog
Sengoku Rance is a masterpiece. And Agarest doesnt have any H content afaik.
That being said, i dont think you know much about eroge.
The "pornshit" you are referring to is called nukige: games focused ONLY on H-scenes (i.e. most of the stuff Mangagamer translated). No gameplay and almost no plot.
To be honest, all the VNs (=Visual Novels) dont have any "gameplay" because it would be useless. You're supposed to READ not to play BUT the good ones do have a plot, obviously (Tsukihime, FS Night)
Then there are eroge with rpg elements. They can be good (i.e. most of Alicesoft games) or bad (Eien no Aselia, Yumina the ethereal) but it has nothing to do with porn.
Porn is just an additional feature, period.
Btw while MGQ is w/o a doubt a nukige, and an indie one, it managed to amuse me because...
It just does interesting things to the usual JRPG cliches (in ways that aren't super grim-dark).
No one should expect anything more from it.
Sure maybe you're getting some good stuff in the best of the pornshit, but if you feel the need to compare the best a merely average 'normal' game, that says it all really
Really.
The ironic thing is...i tried jap (ero)rpgs because i wasnt getting enough fun from those "normal" games of yours, the reason being the lack of GAMEPLAY (and decent rpg elements).
Does the word "decline" ring a bell?