I wouldn't get up in arms if there was occasional raunchy joke here and there. You know, "sixual themes" but no actual six. More so than Oblivion, which was as G-rated as a Disney movie in terms of sixual themes (i.e. there weren't really any).
On the other hand, you get games like Gothic 2 where you get a cinematic cutscene of your character gettin' on with the local lady-of-negotiable-affection. Granted, you do have a dialog choice to avoid the encounter, but still - it's just corny. I know prostitution is "realism" but there are some things from this world that I really would rather my fantasy worlds not stoop to (i.e. forced sixual exploitation of men and women).
Any computer romance would be corny and feel really artificial. I would rather have other non-combat activities, such as an improved blackmarket and underground thieving/smuggling scene; more political scheming, machinations, and plots; mysteries to solve (murder mysteries, and such like Sherlock Holmes style stuff); faction quests and storylines; and in general more personable and unique NPCs that react to my choices in the game world. I'd be happy with more detail for NPC dialog and backgrounds - romancing them isn't a substitute for creative NPCs.
And I don't think the devs could possibly create enough NPCs - both male and female and of different sixual orientations - to accommodate most players who are interested in a romance (though maybe they aren't really picky in the first place if they want a computer-romance to begin with).
EDIT: no graphic six - TES isn't a pormo!