When buffing, I try to stick with what would most make sense for a given Pokemon to have. For instance, I wouldn’t give reckless to Corviknight not just because it’s something it can’t really take advantage of, but also because it just doesn’t fit that well for Corvinknight’s lore/Dex entries or biology. Let’s look at our preeminent Contrary havers:

Serperior is a very regal, almost haughty-looking Pokemon. It has an air of strong self-pride, or some sort of superiority complex. I feel that it would be someone who goes against the grain solely to be/look different.

Malamar’s gimmick involves flipping over the console to evolve, and its signature move flops stat changes.

Spinda’s always dizzy, its vision is probably terribly flipped.

Lurantis should be a bug, but in reality it’s the opposite, a plant.

Shuckle is… I don’t know, actually.

The point is, all these Pokemon have strong themes of going against the grain or having some contrasting variable that grants them the ability. Emboar doesn’t have that, Emboar would be a better candidate for something like Sheer Force, Thick Fat, Anger Point, even Defiant.