For reference, I haven't played DCU, but have played CoH and Champions. 
 
Watching the Quicklook for this game Ryan commented about one of the main issues with ALL superhero MMOs: they give you all the cool stuff (costume maker, power selection, etc) up front and there's no major progression from then out. Despite all of them doing that, I don't think they have to; especially since the idea of an interactive tutorial is the baseline for all games nowadays.  
 
When you start the game you shouldn't get to create your character completely. You create your alter-ego, your everyday Joe. You also select your origin and your personality. These things control your tutorial experience. You begin at level 1 as a regular dude, no powers, no inkling that you are a hero to be. This is where they intro the basic concepts such as quests by giving you mundane tasks related to elements of your character. For instance, if you are a young Peter Parker-type you may work as a pizza delivery guy and have to deliver pizzas. A Bruce Wayne-type managing a corporate empire? Here's some stuff to take to your secretary. Or why don't you sit in on a board meeting and listen to it drone on... None of these have to be particularly long, but the mundane part of it can be a tool to contrast with your soon-to-be more exciting life. 
 
While out doing one of your mundane tasks you can get caught in some random act of violence (which really should be fairly random) such as being mugged, a drive-by shooting, whatever. This can be the intro to melee combat as you fight for your life with just your fists. But you are a weakling and are eventually overcome. Welcome to the death system. You awaken in a hospital and are released, lucky to be alive. Your character rejoins the world a bit more paranoid and perhaps buy himself a gun and goes to the shooting range. Here we can intro the ranged attack concepts. Does he get stuck in traffic on his way home? Perhaps that could intro crowd control. These are just examples of possibilities. My ultimate goal would be that there are multiple ways to accomplish these same tasks and it all differs depending on the personality traits, etc of your character that you picked in the beginning. Ultimately they teach you the basics of the game while never making you quite the superhero, but being a fairly unique and engaging experience none-the-less. 
 
And then the fun begins (and I know the implications of me having said that). I would assume fairly early (eg: arbitrary level 5) you would have completed your "basic" training. Did you pick becoming radioactive as your origin? Or gadgets? Do you get hit by a meteor? Get bit by a radioactive hamster? Whatever it is you chose will happen to you, you watch an in-game event occur around your character that relates to your chosen origin. At this point you pick your first power-set. Spend the next couple of levels learning a few of the basic powers as you uncover more of your capabilities. As you approach arbitrary level 10 you have become accustomed with some of your new powers and used them to perform both good and bad deeds to give you a taste of what life is like as a hero and as a villain. Something major happens which makes you hit a crossroads in this so far ambiguous path: villain or hero? And thus you make your decision. 
 
And with great decisions come great... rewards? Here is where you make your first costume and choose a travel power. This is a "ghetto" costume. Fashioned from everyday items. You are not wearing form-fitting tights with elaborately embroidered logos, you are wearing a hoodie sweatshirt with a handstitched off-kilter logo. Your mask is a spraypainted hockey mask. Are those jeans? There are enough options here that you can begin to craft some semblance of your final costume, but its gonna look a bit "homemade". You can unlock your more exquisite costume options once you've made a bit more of a name for yourself. I would say, ideally, once you are able to join a supergroup (arbitrary level 20). This will be when you can finally unlock all the truly elaborate costume options for your character. in all honesty though, since fiddling with these costumes is one of the big draws of a superhero MMO I think it would be a great idea if you could access the costume creator as a stand-alone menu. You could then save designs (of both homemade and final types) for when characters reach that point. 
 
Around level 15 is when I would have you unlock your secondary powerset (one related to a standard role for group functions: tank, heal, crowd control). This gives you 5 levels to learn some of your new powerset and its tools before joining a supergroup and being to run truly group content (dungeons, etc though if you want to group up with individual players to tackle overworld quests prior I have no issue with that). 
 
With this you have slowly built your character by level 20 and it feels like more of a natural progression and story than the current retcon stuff in superhero MMOs. I would hope it would make you relate to them more. You can still have plenty of content beyond this arbitrary level 20 and have new rewards. What superhero doesn't want a superhero vehicle (batmobile, flying pink unicorn)? What supergroup doesn't want a moon base? There are other ways to still give you something to progress towards.

I love your ideas man! They were the same as mine! I also have more ideas, I'm trying to create one with my own Superhero and Villain universe. Maybe one day we'd work together on this!

Oh, wow, this post didn't get any love 6 years ago? It's a really rad concept for a superhero game.

Shame @averhoeven hasn't been active in 4 years and may never see that his post got comments.

@tom_omb: Really? Tht's sad :'(

I really wanted to share some stuff...