Hmm, usually I will shrug off cinematic tweaks to a story as serving the needs of a different medium. Still, the first Hobbit
movie ought not to have any romantic story in it, because romance was not part of the tale. Tolkien was decidedly old school about certain things in children's stories. Maybe we could get through at least one film without the obligatory boy meets girl scene? Too much of it takes away time from the real story, and too little of it is ridiculously obvious tokenism. (Yeah, yeah, I know, this is Hollywood we are talking about, I'll just end up playing Canute again.)
Now, a brief romance scene played for laughs might work, in Bilbo's case, anyway. Having a brief bit at the beginning of the film with Bilbo Baggins being considered a desirable bachelor catch, and then have him dropped from consideration after his disappearance and strange return would be good for a chuckle or two. (He's ruined his prospects, ruined I tell you!
The chances for success in the second, LOTR-prequel film are much better. The tale of Aragorn & Arwen makes good Hollywood-style cinematic hearts & flowers stuff. Following the path of a few fanfics and making "Thorongil" the unintentional rival of Denethor for the fair lady Finduilas would be good for a good triangle subplot, to be nicely resolved by Aragorn disappearing into the wilds again.