With Caulderone’s build above, I would drop the Invisibility pool completely (it’s really only being used as two mule powers), move combat jumping a tad further down the build and move taunt somewhere between 14-20. Also, take a look at some of those Luck of the Gambler slots being used in the Defensive sets. You may be able to play around with those to both have the Defense that you want plus have a slot to that Shield Wall Proc later in the build.
Bear in mind that I build with Exemplaring in mind, so you can certainly pick up Taunt later in the build if you prefer. That build is an excellent starting point; load it into the Planner and adjust it to taste.