I think alot of people like the "story" (heh dont know what else to call it) element alot, but I agree with you... video games are suposed to be more than pretty pictures and text.
for me the coolest sex games are those where sex is an actual mechanic of gameplay, as in they are in game animations/events that happen as you naturally play the game, be it combat or story choices.
for example games that have combat moves with sexual attacks/initiations/strips/etc or games where you have sexual expertise/moves to develop to have the upper hand sexually against your opponents or story characters.
so far in that regard the coolest was illusion's Yusha, where you have to fight heroines that are initially stronger than you, but you can hold them off during sex, by taking charge during hentai events (by exciting them or using special abilities to hold your orgasm until they have theirs, or bind them etc) as you level up and increasingly become sexually dominating.
close second are simply games with good artwork and animations with in game sex, much like ror games (shinobi girl being top of the lists)
visual novels work, if there are actual story choices and at least decent hentai animations.
games that are pixelated, have no in-game hentai, and have no animated hentai scenes are pretty much a no-no for me, so all rpgmaker games fit into that category :<