Thank you for your review, Blue: This is just a preliminary response while I'm working through the points you raised.
A final note of my own: I tend to suffer from the succinct writing style, which in this character is exacerbated by the fact I know what I want out of him and what he is where you don't. I prefer to build my characters over time rather than present them as they are outside of manufactured developments: it gives me a freedom to shape the character along the way, in my opinion it develops the character more organically. I'll be adding in more information to establish who he is now as you asked.
I can go easier on the allusions stuff; it's really just there to make it clear to someone else what he's based on, which is to say the idea of a Messianic figure and the breadth of the House of David through the old testament. But what I seem to be failing in is illuminating how much of a figure he is, and not an actual Messiah. I don't have to remind you that there is no Messiah in RWBY, at least in name, but the magnitude of his inspiration is limited by the fact that both you and I know that he is a minor character in the grand scheme of the sub. Sure, he's designed to make some waves, but I'm definitely not gonna try and instate a religion or demand to be the main character in anything, which is what I feel you might be afraid of as a moderator.
A lot of my weaknesses in a character sheet are made up for in my roleplaying skill, at least in my opinion, and that doesn't show up in the character sheet. But the inspiration isn't what it seems to be: he's not Jesus, he's a Messianic figure, which means that he hits the tick marks: powerful presence, flashy Aura powers, strange metaphysical happenings, and the like. He's not actually the Messiah, he just really looks the part. That's a facet of the character that's really hard to explain within the confines of the sheet. I suppose a large part of the miscommunication is the nature of Adom as a Messiah figure: he is or isn't depending on who you ask, and as I see it a lot of that is due to my subjective and overall more omniscient perspective as writing his character. As example, your question of "why does his brother mean so much to him," I think "it's his brother who practically raised him, and was brutally killed in front of him when he was 7? What's there to say about his relationship with his brother?" He's natural to me and my perspectives, whereas to others, he may seem a faulty construct, because you don't see why there are pieces where they are, there are places where you feel something is lacking, and the parts that I wanted to be obvious seem too obvious to you.
In the end, however, it is a character idea that I am desirous of playing, and I'm willing to sacrifice much in order to have the opportunity to use him. I just want it to be clear that I am not someone who takes roleplaying my characters lightly, I am not someone who makes their characters lightly by my own estimation, and I am not one of the members of the community who you should be afraid of trying to abuse the system to an excessive degree. I know what I want from my character, and I want that to be clear from the start of the review process. I'm more than happy to answer any questions about why things are the way they are in the future, and I look forwarding to making Adom into something we are both happy with.*