Just because your toes/heels show doesn't mean you will have toe/heel drag. I'm currently using a NS Premier f1-R, with a 25.6 WW with size 12 boots and I'm fine. I'm borderline, but I never have ANY toe or heel drag. If your board is so wide that your toes and heel don't show over the edge at all... then you'll have a little trouble with edge to edge travel.
To the OP, yeah, definitely get a wide.