Sure rogues get a boost from this but fighters and barbs get a bigger one as critting with their high str makes a much bigger difference. I think the Str based rogue is an uncommon build. At any rate, we are in agreement that we are not certain we like the idea.
To reiterate, I think rogues are masters at accomplishing goals with out fighting. Those are the elements that need boosting but right now it seems like everything is tied to killing everything.
And if they are going to insist that everything must die, let rogues sneaks have a chance of killing something outright. In PnP, if you could sneak up unaware on a squishie, a lucky blow could kill it. There is 0 percent chance of a lucky strike doing more than 25% damage on a level appropriate mob in this game. Why is it not overpowered for a mage to stand 100 ft away in hallway and FoD a 500 HP mob but for a rogue to painstakingly sneak up on that mob and kill it is just wrong?
Perhaps add a different level of sneak attack (since "don't have agro = sneak attack" is DDO house rule) where by IF the MOB is not agro'ing anything (ie. unaware of the party) the rogue has a chance (say 25%) at a 'coup de grace' instakill. That is really what Way of the Assassin should be in IMHO.