Okay, I get that this is a joke post, but:
Clock FMC would be too easy and you'd see pretty much everyone get the same solution. (Note: I don't actually have a clock. Not the Rubik's Clock, nor any real, y'know, clock.)
Squan FMC would be impossible to hold with the current two-phase scrambler (everyone would conceivably use CSP, which is basically the second half of the scramble sequence), but this is easily worked around: generate an optimal scramble sequence and tack on a bunch of random moves.
While we're on unconventional FMC variants, big cube FMC would be cool but also impractical. 6FMC and 7FMC are immediately out because misscrambles are too common and it would be super boring if the DNF rate will be sky high because nobody can get the scramble right. 4FMC and 5FMC don't exactly fit in one hour, but making it longer would be logistically complicated.
So… kilominx FMC?