Here's the thing. Men In Black started out as a popular urban legend, then a few comics books (which I haven't read), a movie, a cartoon, another movie and that was it.
None of these were particularly good. The first movie did not do a great deal with the concepts. The cartoon, which can be reconciled with the continuity of the first movie if you grunt a bit, introduced several interesting new science fiction elements, touched upon the origins of the MIB (and Kay) and ultimately ended with MIB revealed to the world, but was not seen by many people and relied substantially on slapstick and recycled elements from the movies - the dog, Jeebs, the worms, the dog, Jeebs, the worms, over and over. And the second movie was the first movie with dittos, only substantially more incoherent thanks to poor editing.
AND YET... the neuralyzer device used in the films has gone down in history as one of the most iconic devices in cinema. Everybody remembers it. It wasn't even that good a franchise, but the neuralyzer and the sunglasses... they worked.
I think MIB is a franchise which can be built up substantially. There is obviously a larger universe here and it's quite an unusual one in that Earth functions as very much a backwater on the galactic stage. I'd scale down the gratuitously gross monsters, bulk up the politics and intrigue, make it smarter. One idea I have offhand is to introduce mysterious Men In White, who operate on Earth, but even the Men In Black aren't aware of them...