Oh yes, im a fan! I personally am kinda done with d20s and have moved on to lots of other systems myself. As to the d6 and the 6 theme- you could do something even more clever but it would mean reworking the system some. In Year Zero SRD they got two systems, one of which is a d6 pool system too but success are only 6s. So you only need 1 for normal success but you have to score a 6 to do it. It makes things more intense and brutal but fair enough especially if build a PC towards the certain skill. Just a thought but your game is pretty balanced already.