FF could be successful with a campy Star Trek feel... (where there is some over the top psuedo-science behind everything... the super-sciency aspect of Reed was sorely missing in the FF films). However, it might be a weird move to reboot the franchise in such a drastically different mold. I am not sure that people would be into the franchise at all, much less with such a different twist.
Maybe it would work... I would like to see it.
But I really think the best way to reboot the FF is to move on to the next episode, and retcon certain details. Have Reed obsessed with trying to find out what is going on with Galactus and SS now (an event like that would pretty huge, even for the mass intellect of Reed). And definitely play up Reed's mega-brain. Fix Sue altogether, but Thing and Torch are usable as is (though I would like some CG to up-size Thing... if only to make him broader).
Now, Reed is spending all his time pouring over astonomical data... They are preparing to make new expeditions into space, this time with Reed's own financing (he came by the resources, perhaps through some govenment work and patents, to produce his own craft). Then off they go... then any number of astrological phenomenon could occur (run-ins with the Skrull, The Watcher, the Celestials, the Inhumans, the Deviants, the Eternals, the Negative Zone, etc...) Thwarting Galactus in an attempt at another planet could be good... this time they determine that Galactus is targetting another planet, and enounter Terrax in trying to save the planet. This coul fold SS back in, and save him as a possible franchise.
All the while, a re-write of Doom could take place as a sub-plot... Play up the details behind Doom becoming the ruler of a independant citi-state in Eastern Europe. Several countries released some territoty to Doom in return for advanced technology. Reed mentions that he is troubled to find this out, because Doom is obsessed with power... This would not be terribly inconsistent with what happenned before (as not to confuse casual movie-goers), but primes us to go in a new direction with Doom for future films... Then in a future film, the full retcon to how Doom is supposed to be could be established.