So it's starting to sink in for me that traders like their interface crowded!
I originally wanted to put the order history on the right like Xeldal and yellowecho have done, but felt there was not enough space. Are we really ok with only providing the quantity and price for the order history?
If the depth chart really isn't that important we can probably either provide a switch between it and the price chart, with the price chart as default, or make a small one like xeldal did.
One thing you guys are forgetting about is the list of open orders, which is below the buy/sell/short/cover tabs. Don't you want that visible at all times? If not we could make a modal for confirmation, but like troglodactyl said that will remove the possibility to short and buy to yourself at the same time.