>>102763406OP seems to think that slapstick antics is the defining characteristic of Deadpool which misses the mark.
The interesting bit about Deadpool (which you might or might not find interesting from a personal perspective) is the juxtaposition of a trained killer and mercenary being over-the-top goofy. The personality doesn't seem to match the job/role.
That discrepancy doesn't exist for Plas, there is no jarring nature to a cartoonish shapeshifter behaving cartoonishly.
Harley actually is a decent comparison, the goofball disciple of a mass murderer.
In other words, OP completely misses the point.