Considering this game is a version of a game first made on the SNES, Players didn't really put much stock into the romantic subplots as they do these days, Jonny. But in all honesty DQ IV was the game with the more developed characters, each with their own chapter and "thing" to do (which served as a sort of RPG Challenge. What if you only had a fighter like Ragnar? Only a Mage and a Healer? Survive Taloon's Chapter as he randomly does weird stuff?).
What amazes me about both of these games, particularly DQIV, is the depth that they enjoyed on consoles as basic as the NES. A lot of the things we think are modern conveniences and innovations of the RPG genre, were actually old hat and been there, done that on the NES. Even grim tones, like the hero/heroine's chapter in DQIV (Yikes. And we thought modern games could get dark and depressing)
I played my brother's copies of these games on a lark and found myself mysteriously enjoying an old-school RPG, despite my hatred of grinding (which rears it's ugly head in the late stages of both games, sorry to say.) And maybe it does have something to do with the fact that the characters are a little more simply portrayed than today's brooding, gravitas-laden, store-bought tragic heroes. And that's thanks to the Toriyama art that always makes things simple for the viewer (which is not to say bad. there's a reason Dragon Ball and Dragon Ball Z are the most popular Japanese Cartoons this side of Pokemon.)
As far as the female characters... eh... that goes back to the medieval thing of courtship (which is why the father gives you a dowry, as a "payment" for taking on the responsibilities of a wife, and consequently a burden of another mouth to feed, should that be one of your concerns and one of the "ways you see it.") It is kind of sudden, but then again, so is most romance in fiction, and watching relationships develop on screen is tiring enough sometimes, but "playing them?" And besides, the world is about to be destroyed, or something. Time's a-wasting!
As a final note: does this Toriyama guy like Playboy Bunny costumes or something? They are all over these games. Which is not to say I mind (grr-r-r-rowl), btu their frequency is more than a little disturbing.