Dominance and recessive relationship of alleles
Phenotype determines dominance. The "rules" you state are just general possibilities that are most likely; they are not correct definitions. "dominant as wild type most circulated" is just completely totally false.

It's common to have mutations that cause loss of function. These often end up as recessive alleles, because the second copy still makes a functional protein. It's not about the allele being suppressed necessarily, and doesn't have anything to do with benefit or not, it's just that the other copy is able to do the job, so you don't see much effect. Because there are often feedback mechanisms for gene expression, having 1 less copy in the genome often means much less than a 50% reduction in protein.

It's also common to have mutations that cause negative gain-of-function: these are often dominant, because you only need one copy for that negative effect to be observed.

However, as you point out, these aren't always the case. You could have an allele where loss of a single copy causes a deleterious phenotype. Sometimes these might more appropriately be considered "incomplete dominance."

I think it's important to note that these terms are really labels based on phenotypes, they are not biological realities. An allele could be thought to be completely dominant, but under further study actually demonstrates a form of incomplete dominance or co-dominance.

The Wikipedia page on dominance has some better definitions for you.