I believe that Scoundrel is not worth maxing indeed, as it does not impact your damage as much as Warfare does.
Regarding the Glass Cannon thingy, with the change to Aerothurge stuns, wouldn't it be viable with Stench ? Play Dead might also be a major tool as a Glass Cannon rogue.
I'm not sure, but I think that the AI prioritizes killing Glass Cannons more than it does running away because of Stench. It should be easy enough to test once you get into Act 2.
I don't see Play Dead as being a useful tool for Glass Cannon. While dead, you're not contributing. When "alive", you're considered top priority and are targeted.
