goneferrying,
The only problem with your idea is that SIDs do not guarentee minimun terain clearence single engine!
Operators of high-capacity aircraft have to have single engine procedures and "escape route" even at airfields with SIDs. You will note many SIDs havve minimun climb gradients published on them. The designer of the SID has no way of knowing whether your aircraft can meet those gradients. It is up to the operator to ensure the aircraft can, or have an alternate procedure if it can't.