After some consideration, I would say my favorite romance was in Ar Tonelico II.
It is a criminally underrated JRPG with some prominent visual novel elements, and even though I admit it has flaws, and by that I mean actual flaws, not the whimsical gameplay elements and the sexual innuendos scattered around that some people couldn't seem to get over, but it has one of the best cast I have ever seen with great character-development and romances that actually take a lot of time, effort and dedication to develop.
Also, I couldn't help but notice that a lot of people mentioned Katawa Shoujo which, while a unique and interesting story, wouldn't really be the first example that would spring to mind when I want to talk about romantic visual novels.
Also note that in most visual novels tying a a plot/scenario to a heroine/love interest is pretty much a convention, even in the most plot-focused VNs. As such I would say it is a pretty good medium for anyone looking for more romance-oriented works, though they have a tendency to be extremely formulaic in their own way.
Finally, for Skyrim/Fable, you guys are missing a crucial point: those are not "romances". In Skyrim it is pretty much spelled out that finding a spouse through the amulet of Mara is not really about love but about convenience, both in-universe and in game-mechanics. It compares better to arranged marriages where both parties get something out of the deal and has nothing to do with the feelings of the participants.
Oh, yeah, and Skyrim actually has one awesome romance: Serana in Dawnguard. Sadly Bethesda messed it up pretty hard by not allowing her to be married, but if you choose the right conversation options throughout the Dawnguard quest-line, it becomes blindingly obvious that there is a lot of chemistry and affection between the Dragonborn and her, and this romance actually makes a lot of sense taken just how much both of them rely on the other.
As for Fable... Pfff... It's a joke, really. In fact, the "romance" in these games are so pointless it makes Skyrim's marriage look downright heartwarming in comparison. At least in Skyrim you had to friggin talk to someone and do a quest for them before the option came up, while in Fable you can walk in a town while being 100% good and just throw a wedding ring to the first person who you meet (and who will immediately fall in love with you for some reason) without even knowing their name!