Sure!
Here is how I currently see things:
1) Yes, The Gold Phoenix version is Giraud at his highest potential or ultimate form within the Crown.
2) There are many other Phoenix within the Crown. Some have costumes that do not mean anything, as they only wielded the force for a small, specific time or adventure. Purpose was short, defined, specific. Others may have tried to take or steal the force and their costume is unremarkable. Maybe the PF tried to bond with some ONLY out of necessity being dire, but it really did not want to. These "Phoenix" would likewise not have any special significance. These costumes can be anything, such as a person's usual costume with a Phoenix on it or a Phoenix costume in all different colors or a mix of colors. These are just preferences of the host or wielder.
There can be Green Phoenix hosts where they were in control. Red would be loss of control and giving into the person's dark side/desires as Dark Phoenix.
We have The White Phoenix of the Crown, the highest level a host can attain. Jean is the only WPC.
Giraud will be the only Gold Phoenix as that is his special significance within the PF, but which also allows for him to bond with the Cosmic Rival Power. He thus has a special role and in the WHRoom, he will deal with the balance of the two and using both to accomplish tasks, whereas they normally would not/would not be able to work together.
[When it is acceptable, we need to go over what the Cosmic Rival Power is in detail so that I ------and then later the others----will be able to understand that aspect.]
3) Yes, the Crown is full of mysteries and mystique that we cannot hope to understand, let alone explain or show to mere mortals! Much will still be that way, hidden and mysterious!
4) Giraud will have the powers of both the PF but also the powers of the Cosmic Rival Powers. In our Universe/Multiverse (oh no, not that again, lol!), no one but the Cosmic Rival Host can understand, accept, relate to or use the CR power. Except for Giraud. He can as well. He will help that Cosmic Rival Power/Host be able to exist and work in our side of things, which is a constant challenge and is ongoing.