I don't think there would have been. As people said, they seemed based on the glatorian and element lords. I've always suspected though that maybe the skakdi were failed toa. They don't seem to provide any function to Mata nui (unlike other things), and they're similar in strength to Toa, and are capable of using element powers (albeit only together). I think the element use of skakdi may have been meant as the great beings stressing the unity aspect. Maybe they were too violent though and abandoned for current model of Toa. No supporting evidence, but just always something I thought was so crazy and out there, it could be true. Canonically though, I think it's implied that helyrx is the prototype Toa. I don't think Toa Mata qualify, since weren't they created by Artakha (not the great beings much later? Edit: Nevermind, I forgot that it was implied that Makuta Spiriah gave them their powers. It never specified what powers however, so I still think it might be interesting if he only gave them secondary powers such as avak's cage ability, or vision powers. They may have had element powers all along, or maybe the great beings sealed their toa powers and spiriah just unlocked them