Equality works well with Equivalence Mythic, as the Mythic evens out your HP/MP to equal values automatically. otherwise YOU have to make sure your HP/MP is even.
I have also used it with Alchemy Mythic. I just had to make sure the HP/MP was equal.
if you use Glasscannon or Barbarian by themselves, that will ruin your HP/MP Equality%, unless you use one of each. as long as they are both the same amount, you are ok (45% for each of them for example).