Superman Can Bugger Off Again

Finally saw Superman Returns the other day. I'm still not entrirely sure what I think of it, but I'm leaning towards massive disappointment.

Anyway, here are some questions it threw up (note - spoilers within):

1. According to Marlon Brando in that recorded message, it took Superman thousands of years to travel to Earth. So how fast can Superman fly then, if he was expecting to go and find Krypton? Or was he expecting to be out there for aeons?
2. What did he eat, and what did he breathe in space? If they're going by the standard, 'He gets all his energy from the Sun' mythos (which I've never really liked - why does he have a stomach then?), then that explains the food thing, but he has to breathe, doesn't he? Even if he took some oxygen with him, it wouldn't have lasted him five years.
3. Five years alone in space? He'd have gone mental surely?
4. How strong is he then? There have to be some limits on his abilities. And why - if it was such a struggle to stop that plane - is he apparently able to lift an entire island (infused with Kryptonite no less) up into space?
5. Why did they go with the comedy Lex Luthor approach? Kevin Spacey appears to be on a permanent piss-take throughout the film, an attitude he seemingly carried through the publicity tour they did for it. Lex Luthor was always a more interesting character to me than the infallible Superman, and after Michael Rosenbaum's nuanced, more abiguous turn on Smallville, it was a crushing shame to see the character revert to swaggering tosspot.
6. And why give Luthor another ditzy sidekick? There are some throwbacks to the earlier films they needn't have bothered with recalling. Indeed, in many ways it felt like a film from the Eighties, and not really the update I was hoping for.
7. Everyone was thrilled to see Superman again, but no-one seemed to give a stuff that Clark Kent waltzed back into The Daily Planet after five years. And that was one of the main problems with the film for me - not enough Kent. Much the same way I prefer Luthor to Superman, I've always found Superman's alter ego to be the more interesting personality. As Kent, he was probably on screen about 10 minutes altogether, and he almost needn't have been there at all.
8. You can usually judge a film's impact by which scenes and images instantly come to mind when recalling it a few days later. For me, I tend to think of the plane sequence, but beyond that I find it hard to pinpoint any standout moments. And anyone who's seen any of the trailers and publicity clips for the film will have virtually seen the entire plane bit anyway.
9. Does Bryan Singer actually have any pedigree as a director? Apart from the X-Men films, which really do nothing for me, the only other thing of note that he's done seems to be The Usual Suspects, which mainly consists of a load of men talking and trying to make each other laugh.
10. And why do his clothes never burn up on re-entry?