Ok, to put it simply, your goal is to make your HP and MP equal to each other.
Equality increases DMG and all regen +37.5% of your total HP/MP Equality
that means you need to get 1 when you divide them.
in your case 1/76 = 0.013 you get very very little dmg and regen boost
in my build 462/449 = 1.02 thats how you get +37.5% gmd and all regen. That's a big boost your base damage should be around 900K if you do it right
I dunno what you're doing wrong and you only see 20B dmg. I'm at floor 4,300 M3 now and still seeing quintillion dmg.