First question is a bit of a special one. I will show you what you find, it is what your character's get from the discoveries though that is up to you. I will be controlling the world, but it is your characters' decisions that will be affecting it for better or for worse. Of course, it all also depends upon what you take from anything you find. For instance, lets say your character finds some old ancient ruins that hold some dark secret. Do you perhaps uncover the truth and destroy this dark secret? Or do you perhaps try and benefit from this dark secret? It all depends upon what your character wants to do. 

Second question. Yes, but within limits. What types of Traits would you like to create? Traits are like Perks essentially, special passive/active abilities or skills that your character can perform. 

Talents are like your own natural skills like Climbing, Fisticuffs, Acrobatics, and other such typical D&D esque skills. 

And yes you can, but just tell me your character idea first before you go through a bunch of work to make something special. Of course, if you have a special idea (like maybe you want to be from the Far Lands or a member of some hidden race) I am all for it.