Any potential Clark/Lois romance would come off as vapid and shallow simply because they haven't had time to build up to it. The entire series up to this point have been about the Clark/Lana relationship and a Clair/Lois relationship has nothing going for it but "destiny" and years comic book canon. Forcing it at this point simply isn't going to work.
Seriously, they shouldn't have had Lois in it at all. And instead of years of will-they-or-won't-they followed by obsessive teen love and deus-ex-machina that serve no purpose other than keeping them apart, they should have had a simple realistic romance that gradually turns sour, ending in a painful, bitter, but realistic and natural breakup, instead of the crap that they actually shoveled out. Or, you know, actually had some lobes and let the two of them end up together.
It isn't that hard to write a good five-year-arc distilation of the character, but instead they went for the shallow teen drama, cluttered it up with needless character cameos (Legion of Superheroes, I'm looking at you, and Aquaman, too. And The Flash, And pretty much every other superhero Justice League except, maybe, the Green Arrow, who is actually used half-decently sometimes, but mostly the Legion, because it it is extremely difficult to do time travel right; adding a while group of time traveling characters, even one-shots, damages the universe, even if they are comic book canon), and kept beating it's zombified corpse.