Oh, I could go on for days with this.
I've actually got a big layout for a whole Ultimate DC Universe (a good portion of which I get to play out in the RPG of the same name--cheap plug), but right now I'll stick with Superman.
For starters, I'd use
Birthright as the launching pad for the series (since at one point that was what it was intended to be) I really liked Waid's interpretation of the \S/ mythology (except for the vegetarian bit, but come on--that's pretty inconsequential compared to the broader strokes), thought he did a great job of combining the old mad-scientist Luthor with the criminal billionaire from
MoS, and had my personal favorite rationale for the Clark Kent/Superman identities.
From there, I'd go with my own tweaks:
Power Limits:
Though there's no defined upper limit to his strength, Superman would start with his powers right around the same level as in the Animated Series, and escalate from there. So no bench-pressing a continent without breaking a sweat, but at the same time no getting punked out by some mook with a laser gun.
The Fortress of Solitude:
The Fortress was contained within Kal-El's pod, inside a time/space pocket not unlike the TARDIS from
Doctor Who. It was intended to be a self-contained colony for several thousand Kryptonians, but due to design flaws and simply running out of time, Jor-El was only able to place Kal in the pod. After landing on Earth, its programming would eventually cause itself to move to an isolated location (the Arctic) so as to avoid interference from the indigenous species (us), and extract from the pocket, expanding into the massive Fortress Superman would eventually use as his personal refuge and time-capsule. Similar to the Animated Series Fortress in terms of features, but looks more like Leinl Yu's designs of Krypton.
Krypton:
I've got a whole huge world mapped out for Krypton that I've used as a setting for a few table-top RPGs, and the fanfic in my sig. Long story short, Krypton was an extremely harsh planet about the size of Jupiter, and while Kryptonians evolved to a technological utopia, huge sections of the planet were still wild. The perfect planet for a race of adventurers and investigators.
There were 11 city-states, each ruled locally by a democratically-elected Magistrate, and governed at large by the Council. The Council also employed elite agents known as the Sapphire Guard (think a less-clandestine version of the Spectres from
Mass Effect), under the orders of General Zod.
Once the capital city of Kandor was stolen by Brainiac (see below), Zod attempted to seize power in a military coup, met by opposition from the New council led by Zor-El. Unfortunately, these happenings drowned out the voice of Jor-El, who had discovered the planet's core had grown unstable and would soon rupture. While his brother and Zod battled for their people's future, Jor labored to make sure there was still a future for them at all.
You know the rest by heart from here. Zod's faction is defeated and locked up in the Phantom Zone. Jor-El has a plan to save everyone, but the New Council won't listen. With only moments to spare, Jor places his son Kal in an experimental ship and shoots him off to Earth, while the planet explodes around them.
For looks, the cities would mainly use Leinl Yu's designs from
Birthright, with touches of the crystal architecture from the movies. The planet itself would look like Metropia from
For Tomorrow.
Kryptonite:
There's only the one kind, and it's in very short supply. As shown in BR, it's extremely energetic, capable of being used for all sorts of crazy applications, and a tiny sliver of it can either bring Superman to his knees or blow up a whole city block. Luthor will definitely have a few chunks on hand, as will STAR Labs (one of which is stolen to create Metallo). The JLA will eventually keep a K-ring handy as a 'just in case' weapon.
Lois:
If there's one thing I really liked about the Post-Crisis/
Man of Steel-era Supes, it was that Lois ended up falling in love with Clark instead of Superman. And while I'd also like to see the old rivalry with Lana Lang, as well as the old Silver Age thru-line where she pretty much knows that Clark is really Supes but can never quite prove it, I think makes for much better storytelling if she goes for the unassuming but good-hearted everyman over the knight in shining spandex. Either that, or I'd have her go with Richard White just to screw with everyone
t:
The Bottle City of Kandor:
When Superman first encounters Brainiac (I'll get to him in a minute), he gets trapped inside of a 'Bottle City,' which is actually a portal to a tract of extra-dimensional space similar to the Phantom Zone. Inside it, Brainiac has thousands of cybernetic drones to observe and patrol the city, which he's divided up into three distinct sections.
The first section is the heart of the city, which is left more or less pristine. It's observed for social and psychological experiments, but the people living there carry on with their former lives as best as they can.
The outer sections, blocked off from the rest, are almost
Terminator-like, where refugees are hunted down and subjected to Brainiac's hideous 'upgrades,' looking to create a perfect cyborg specimen.
The third section is deep beneath the city, where thousands of Kryptonians are stored in suspended animation in case the numbers of the surface are depleted. This happens to include Kara Zor-El.
Kal eventually joins a hidden resistance group, finds and rescues Kara, and leads an uprising to overthrow Brainiac's drones and liberate the city. Kal and Kara are able to escape, but are never successful in bringing the city back into their universe.
Allies:
Metropolis Special Crimes Unit: Led by hard-ass Captain Dan Turpin, they're a special division of MPD that starts out as basically an amped-up SWAT team, but over time (and with the addition of all sorts of new tech from STAR Labs), they're able to take down mid-level supervillains on their own.
Kelex: The sentient Kryptonian A.I. that runs the Fortress of Solitude. Can inhabit any of the dozen or so helper robots inside, but cannot leave the Fortress itself.
Supergirl: Kal's cousin from Krypton, though instead of having her just show up in a second pod, she'd be one of thousands trapped in suspended animation, deep in the underground levels of the Bottle City of Kandor. After Supes helps her escape, she progresses more or less like the Supergirl in the Animated Series, first as a smart-mouthed protege, then, during a time-travelling storyline, coming into her own as a full-fledged heroine among the Legion of Super-Heroes in the 31st Century.
Superboy: One of the U.S. Government's attempts to create a 'new' Superman following his death at the hands of Doomsday (the other attempt being the Cyborg), Superboy is a clone made from mutated Kryptonian DNA (giving him his post-Crisis powers) He's eventually freed from the Cadmus labs by the real Superman, but doesn't want to be a sidekick. He travels the world on his own, a la the Hulk, doing his part to help out wherever he can, but trying to keep off the grid as much as possible, before finding his place alongside the Teen Titans, and eventually looking up to Superman as a father-figure.
Legion of Super-Heroes: Rather than just a team of a dozen or so, the Legion is just that: a full-on
army of super-heroes in the 31st Century, an intergalactic peacekeeping force that was founded on the principles Superman represented. Keeping most of the recognizable members (Lightning Lad, Saturn Girl, and
especially Brainiac 5), it's basically the Green Lantern Corps with a less monotonous color scheme.
Justice League- While there would be a few hero team-ups before the League's official founding (particularly groups like the Trinity, or the Hal/Barry/Ollie clique), the JLA would formally organize to help fight off the Starro invasion. They'd start as the traditional 'Big Seven,' then evolve into the huge army-like League seen in JLU, using a re-vamped Hall of Justice as their HQ, and the satellite just for sheer cool-factor.