Reset character achievements at trading, seriously
Character trading via marketplace is destroying PvE. Specially talking about pug raids.
To ask for certain achievement at the moment of inviting someone to your pug raid, is probably the only guarantee you have that this player is worth inviting. And that's totally right.
Happens to me almost in every pug I make or join, that some "boosted animal" comes to Violet Hold in order to be inspected, with his/her shiny Light of Dawn title and bis gear.
Raid is now full, we head to ICC and the same player manages to die on every and each boss. Sitting on flames, ignoring fester's spores, targeting BPC's orbs, tombing everyone at Sindy and exploding from necrotic plague.
This system has turned character achievements into things without any value at all. It takes only a few bucks to buy a character with some decent gear and end-game achievements (or even realm firsts). That doesn't sound good at all.
All character achievements should be wiped at the time of buying it from marketplace.