@Eric Roelofs - we have similar issue where existing sales order after submit scripts add a few unnecessary seconds to order confirmation (which given the poor default UX is really not ideal). I am still actively working on our solution but basically all off our scripts are there to help categorise/tag orders ie. the work they do is informational and has no impact financially on the SO or influences whether a web sale should be successful. So I have reduced the aftersubmit to as minimal as possible