Hello Tabor,
I'll PM regarding some things which I don't want to post here out in the open. One thing I'll say here is that I noticed that every section of this site has a unique set of complicated formalities which take a little too much away from the experience (for me at least).
Anyway, I've never really been up on collecting and trading. As such I don't honestly know what people consider valuable and what they don't, over and above what's going to get you through the game's quest. I also restart too often to really be able to establish enough of a collection to where I'd have anything to offer.
I replied to the response I got from Cid via PM and kinda ran aground there.
Anyway, I'm not sure what else to say, but I'll PM you after I post this.