This one would make more sense as a tv series in my opinion.
make it more of a comedy / cop adventure
That's what it is already, no, a buddy-cop-action comedy?
The MIB premise is so simple that it could be taken in numerous directions. Will Smith has a charming, funny screen persona, but the series easily can continue without him.
Sony and Amblin have been trying to figure out the best way to relaunch the series, after the original pairing of Tommy Lee Jones and Will Smith ran its course in the 2012 third installment. The attempts included a spinoff film that would meld Sony’s 21 Jump Street cast members Channing Tatum and Jonah Hill into an extraterrestrial spinoff. This film isn’t that one. Rather, it is a spinoff grounded in the original premise, of a covert force policing the alien population hiding in plain sight, the premise of the comic book series by Lowell Cunningham and Sandy Carruthers.