D.O.M.E. is Franz Hopper.The guy always finds a way to return from certain death at his own altruistic hands. This means, of course, the following:
Garrod Ran is the non-Newtype reincarnation of Judau Ashta from Gundam ZZI CANNOT be the only person to have noticed the similar jackets and the fact that each pilots a Gundam with a 1-character name (Gundam X, Gundam Zeta) and then upgrades to a 'double' version of the previous one (Gundam Double X, Gundam Double Zeta). Additionally, the Double Zeta added a mobile suit-mounted Wave Motion Gun, which the X and Double X incorporated. As for why Garrod isn't a Newtype? Judau wanted to see how good a pilot he could be without his Newtype abilities when it was his turn to be reincarnated.
The Frost Brothers' Gundams are named after DemonsEverywhere I look, Shagia Frost's Gundam is named "Virsago", but when he said it, it sounded more like "Vasago". Well, Vassago (double s) is a demon prince from a 17th century grimoire called the Lesser Key of Solomon. Now, while I can't pin down the original source of the description (Google returns a lot of results), one of Vassago's forms is supposed to be a red dragon with green eyes. The Gundam "Virsago" is red, has draconic features, and has green eyes. Finally, also in the Lesser Key of Solomon (going by Wikipedia, anyway; I don't exactly have a copy on hand) is another demon named Astaroth, sometimes said Ashtaroth, which is pretty close to Gundam Ashtaron. Furthermore, Vassago is supposed to be a prince, while Astaroth is supposed to be a duke, which can be ranked below a prince assuming the prince is a monarch. This would fit with Shagia being the elder brother, and Olba being the younger. Given, Astaroth is never described as looking like a one-eyed crab (though that would be kind of awesome), so the comparison isn't perfect, but at the least it's a freaky coincidence.
Garrod's Father designed the a GundamWhen asked about his past by Tiffa, Garrod doesn't recall much, however he does remember that his father was a Mobile Suit engineer who basically got lynched after the 7th Space War. Given the time frame it is unlikely that he designed the Double X, but the original GX-9900? That is not entirely out of the question, especially when you consider that at episode 30 the writers for Gundam X found out they only had 9 more episodes to conclude the series instead of the standard 50.