I think you have gotten some good advice in this thread, and as an evangelist for the project, you need to put its interest above your own frustration with the way that advice is packaged. You should be courting supporters, not riling up adversaries.
The only things I can quickly add to what others have said:
(1) "Courier quest" is pretty
common usage for a boring quest in a cRPG. So the game's subtitle may have negative connotations for yo developer friends' core audience of seasoned RPG players. This isn't to say that actually having the PC be a courier is a bad idea. It might actually be kind of neat to have a Pony Express feel to things. But I would keep it out of the title.
(2) I guess I might also offer a counterpoint to
Vault Dweller's suggestion about fleshing out ideas more: in some instances, I think
less text would do better. I don't know that specifics like occupations and sense of humor, for example, add much. A more impressionistic take on the races would serve to whet the player's appetite; too much detail just gives people things to nitpick.
(3) Given that there is a "screenshot" (mockup?), I would leave out the standalone renders.
(4) I'm not sure quite what's going on with the "Black Geyser" title, or how a Geyser will crush you. I thought the emphasis on greed was more interesting, and I wonder if your friends could build a title around that instead.