It has been over 6 years since I've played a build with more than 2 levels of Rogue so my thoughts on the Enhancement Tree won't really be of any use because I don't know what they are to compare to where you are going.
However, I can comment on the Trap and Grenade making side.
One of the reasons why my Bard/Arti/rog build has 4 levels of Artificer is for the Trapmaking skill. I like the idea of making traps and setting them. I like the direction you are going with traps and look forward to what is available for the Epic Trapping.