We can go to a text based centralize system, but it'll just sound too much like an auction house.

UI lag though is more of a problem with the fact you're selling such a large volume...most MMOs have UI lag but it's "hidden"

A better method would be to have a "cache" follow by and ok/cancel option.(drag everything to the buy/sell window, then accept, and it processes everything in one go) Of course I guess SE doesn't want to risk dupes or something by locking down their safety procedures.