It was explained that the reason Dorry and Brogy's initial bounties were so low is because of the natural inflation that happened over the century, which I always figured was a logical explanation for it. It's clear that Oda always wanted us to view those two as beasts, hence they had feats of blowing through the Sea King and lifting the giant skeleton on Little Garden that still hold up in the post-skip.
Loki looks badass, would be cool if the DF is a Norse mythical. Perhaps something like Hebi Hebi no mi, Model : Jörmungandr.