Maybe since Lucas had to work harder on the OT it turned out better. People usually produce better things when they are under the gun. With the PT he had it pretty much smooth sailing. The technology was there to give him all he wanted.
As far as being older now. Yea, I see your point and I can see it backed up with my own kids. I have exposed them to as much as the OT as I can but their preference is the PT. My son loves watching little anakin racing in the pods. He loves all the stupid little jokes that happen in the PT. He loves watching the Jedi's dish it out to the baddies. To him it's all about good vs. evil, nothing more, nothing less. The real thing that saddens me in all of this is that thanks to the PT he doesn't see Darth Vader as the bad ass that we all so him as. To him it's just anakin in a suit and he'll be good again so it's o.k.
But back to the topic at hand. An expanded universe film or show could be done correctly as long as it returned to the roots of any good movie. Character development and story telling. I believe Lucas could pull this off and I hope he does with this SW t.v. show. But there is the old saying that lightning doesn't strike in the same spot twice and that may be the case for Star Wars.

On another note completely off the subject. I just wanna say I love this site. I've visited alot of the other SW's sites and none of them reach into these movies like this one does. I've been reading these forums for the past year now and the things I've learnt here about SW and editing has been awesome. O.K. cheesy part over.