I'm sorry, but I always hated Man of Steel. The whole dystopian Nazi-eqsue Krypton in particular left a really bad taste in my mouth; if Krypton was such a terrible place, then why the hell would Kal-El care about commemorating it?
It wasn't a terrible place at all. It was simply cold and unemotional, which was meant to be Byrne's way of showing a more tragic version of Krypton than that of previous versions of Superman's orgin.
Seriously, the whole concept was that Krypton's society didn't
have to be like that, and just as one of its citizens (Jor-el) gets that into his head and starts to change the way the world thinks for the better, it's already too late since they're all about to blow up anyway. Jor-el didn't just want to save his son from an exploding planet; he wanted to save him from their cold way of life.
Stripping his powers down and making his costume to be designed after the JSA heroes just does more to make Superman less special,
I'm not sure where the JSA influence you speak of comes from, but it sure wasn't mentioned in "Man of Steel."
And the powering down was done to humanize Superman more. Sure, he could still move mountains and stuff, but he was just weak enough to bring the character much more down to earth than he was before.
as was the transformation of Lex Luthor into "Kingpin Lite." The whole thing just seems like a blatant attempt to distance Superman from a lot of the elements that defined him.
Lex being turned into a corporate tycoon was done to make himself more like Superman's opposite. Superman stands for truth, justice, and the American dream, whereas the Businessman Lex stands for lies, manipulation, and warping the American dream to suit his means and allow him to tempt others.
DC already had a dozen mad scientists at the time, so Lex had to be something special and not just another one of those schmucks. Lex became a whole lot more. He became the man who used those other scientists to make something for him, corrupted their creation, screwed over the scientist, and then had the scientist in question take the fall for the whole thing once it fell apart after it fulfilled its purpose.
To me, that's much more evil and menacing for Lex to do, rather than being just another carbon copy from a long line of generic mad scientists.
As much as people whine and moan about BR having the "soul vision" (which barely factors into the story at all, aside from making Superman more dead-set against killing) or Luthor showing up in Smallville (which has been in-and-out of continuity since the 50s), Waid at least tried to stay faithful to the classic mythos, whereas Byrne just seemed to be changing stuff merely for the sake of changing stuff.
Personally, I don't see what the big deal about Soul Vision is either (it just makes sense that a guy who can see pretty much the whole EM spectrum should at least see
something that's there when you're alive, but gone when you're dead), but changing Luthor to fit into Clark's youth in Smallville takes away from Luthor being involved with Perry White's youth in Suicide Slums.
Given the choice between those two options for the story of Lex's coming-of-age, I'd definitely choose Lex & Perry in Metropolis. It makes for a much more tragic, yet evil, interpretation of how Lex came to be who he is.