Cross Guild exists primarily so that
a) Oda can make Zoro and Mihawk have a genuine fight where they are both pitted directly against each other
b) Oda can keep Buggy relevant EoS
I don’t think they need to get to Laugh Tale for either of the above to be true, and I also don’t think that Buggy being a general figure means that all of Cross Guild has to be as well.
Buggy’s reawakened dream of being the PK was also played straight, it wasn’t shown to be something to laugh at. Of course he’s never going to achieve it, and Buggy will always be primarily a comedic figure, but that does not mean he can never have serious moments to off-set the comedy.