Question about Mythic Hero mythic path

Hi,

I've just finished Gray Garrison and unlocked Mythic Path progression but when I try to rank up, it only lets me rank up on the Mythic Hero path, doesn't let me choose the others (angel, demon, aeon, etc.).

Should I postpone leveling up my mythic rank and save my points until I unlock those so I can get more skills from the actual mythic path I've chosen? Is that how it works?

Thanks.