If there's one thing about Dana White I can comment with a perfect knowledge, it's something that any famous celebrity can learn from. Dana White treats the fans with respect. When I went to UFC 108 we rented a pair of binoculars to see people sitting around the ring. We saw tons of fighters "in attendance" but what amazed me most is that I never saw Dana White sitting down. He was always walking around, talking to the fans, signing stuff, taking pictures the entire time. There was one fight I got bored with and was looking around and during the fight he was taking pictures with this huge group of people. The guy cares and respects the fans like nobody I've ever seen. I used to respect him for where he has taken MMA and what he has done for regulation on MMA in the US, but I respect him for his devotion to the fans. That's hard to come by when someone is "drunk with power".
I agree with some of the points about DFW being too quick to jump the gun on some of his decisions, but your last sentence sums it all up for me and I feel the same way you do.
DFW has done so much for MMA, and who knows where MMA would be today... for all we know, MMA could have turned out to be like the WWE with a bunch of silly-ass cartoon-type characters promoting the sport.
Then I never even would have become a fan... so my answer is, No DFW should never step down or take a backseat as the UFC figurehead.