I have never been a fan of "hub of the universe/multiverse" concepts, mostly because if there are infinite universes, then there should also be infinite connections and therefore, no center or hub! *sigh* But I digress and we are playing fantasy here.
The concept is pretty original; I've seen multiverse RPG's before, but few where you are part of the group that is trying to grow outward somewhat like the Federation in Star Trek. Usually you are defending your world/yourself from the conquesting group, etc.
There seems to be several good thoughts on how characters can play this, and the unique weapon angle is slick. Needs a better written explanation of how they discovered it, but overall very intriguing. I can think of a variety of ways to use this. I also, after reading the comments, think that with some tweaks, this could be a very interesting setting for a game. Or a really good Saturday morning cartoon for 12-yr olds. Not really sure which would be better yet.
The writing is decent; some grammatical and contextual errors, but I get the gist of the concept. There does seem to still be some indecision on some key points, but the overall linchpins are solid and easily modifiable to something the swarm would fully approve of.

Comments
I like this, but this will
I like this, but this will make the setting 'huge".
In many ways, each planet will be "Star Trek's Planets of Hats, ( http://tvtropes.org/pmwiki/pmwiki.php/Main/PlanetOfHats ) or Lucas Syndrome (Each planet seems to have one ecology). GM's can try to customize a few worlds (or have re-occuring visits), but really it is going to be a lot of drive by adventuring.
To head towards Moorcockian boundries....
So we are the agents of Balance. That means there must be Agents of Chaos and Agents of Law, knowing that doing extreme in either direction can lead to bad things. These two forces are always going at it, we get involved only when one wins or looks to be getting a significant upper hand.
These agents have "faces" normal agents in the worlds, then they are pretty exotic when they are in their native form.
There is probably a wild card enemy that has its own agenda and alien abilities, just to make PCs jumpy.
There will be an number of other groups that travel between the worlds and utilize them. Each should have their own agenda. Merchants for some. Illuminati for others.
To be honest, this should not just be a fantasy setting. I mean most world can be fantasy, but you will need room to have tech of various kinds as well (As Alternity showed us, Technology is just another special effect of Power use).
Option: Perhaps the characters "travel to the world" by taking over the body of a being there. This keeps your odd equipment to a minimum. You bring some of your skills and your knowledges with you. Thus character creation should be pretty quick.
Option: If we can embue our people with immortality of sorts. They can only be hurt by "soul", thus bullets, arrows, and blasters, hurt them but they get better quickly. Hand to Hand weapons hurt them some and could kill them, but they can heal it back soon. Straight hand to hand combat might actually be more deadily to them. This pushes towards unarmed combat and a better fantasy feel. This also makes our Heroes better with their cooler martial arts and chi powers.
Moorcockian Styles Rule
First oft, I just want to say thanks, this setting was partly inspired by Moorcock, but hardly anyone knows he is! Anyways, yeah you pretty much hit it on the nail. I like your idea about the immortality of sorts as well as the body snatching but with a possible tweek. I imagined that world travel took place through gates (calling them planets implies space, so I'm going to go back and change the names around), and travel through the gates kind of preped the characters for the world they are going to. Like if the were going to a completely aquatic world, the magic of the gate my provide them automatically with either technology or a biological alteration that allows them to travel underwater. When traveling back through the gate some items may not be processed or may be altered such that some weird stuff won't come across the boundaries of the worlds. No one really knows how it happens, it just does. I do like the idea of the eternal champion though having an existence on all planes, its conscious just more or less travels between them, so we could change that. As for the immortality, it explains why when the characters get hit with arrows or bullets depending on where they are they don't just keel over. Also I was playing with the idea of having the weapons sometimes take on new forms in the different worlds to better blend in. Thoughts? But yes, this is a huge setting (I'm not sure I know how to do anything small scale), but I personally like that as there is plenty of room for us to expand it and plenty of stuff GMs and players can come up with. Well, glad you liked it, and please give it a review! :)
My thoughts
I like the background and the buildup you have. It reminded me a bit of a campaign world a friend of mine has, but yours is still its own obviously. The part that loses me a bit though is the interplanetary aspect.
What if instead of being interplanetary, the setting was multidimensional? Imagine a sort of traditional D&D cosmos with multiple planes of existence and in this case multiple physical dimensions (multiple Prime Material planes in D&D lingo)? Does that appeal to you at all?
Thanks, I'm glad to hear
Thanks, I'm glad to hear that! :)
Actually, that was what I was going for. I honestly was drawing a blank on the multidimensions bit when I was writing it (yet I remembered the multiverse, so go figure). My idea wasn't to have different planets like a SciFi game, but different dimensions / planes like you suggested. I'll go back and change the wording so that is more clear later, and thanks for pointing that out! :)
New Setting
I'm still working on names for this Setting and the names of things in the Setting and would appreciate any input. Also, I plan on organizing the setting a bit better and fleshing it out more later, I just wanted to know if anyone had any suggestions for this setting first.