What i know in order of your questions:

1) Sounds like what a Baron does. Or what a Baron might want to develop. I would suggest a Baron package and finding a Kingdom to work with. Or a friendly Baron already in place who is looking for manpower. It all depends on how much time/money you have. And the amount of control you want over your guys.

2) No Moose yet. Dryas Elk are close. Kind of like giant Irish Elk. No word on if you can tame or ride them. But if you can it would look really nice. Fingers crossed here. Not sure if you can tame for "others", but there will probably be mechanics where you can tame and then sell them or something like that.

3) Nothing yet on how customizable the helmets are yet. Last developer journal did have concept art for Neran armour. Very drool inducing. Hopefully all races get the same detailing.

4) Also not set in stone yet. They say there will be different levels depending on your pledge level (starting at Bloodline). Each is supposed to add more colors and crests and such all the way up to the King.

All subject to change of course, lol.

Each tribe or rather each biome will have it's own standard mount. Horses, Trison ( mix between a bison and triceratops), and I think Otterbears might have been confirmed but I'm not 100% on the otterbear.

Nothing is bound in this game. Everything you have make or find can be given, traded, or taken from you.

If it does not exist on launch it is only a matter of getting people to research it though in the case of adding a plume I doubt research would be necessary. As far as paint I think as it stands artwork or crest etc is reserved for cloaks/tabards and can bear your family crest whose design depends upon the package you purchase.

On guild crests I have not seen anything and I don't think we know much beyond the very basic mechanics on how they will operate.

thanks for the replies guys you've helped alot :D