One thing that I think really differentiates DC from Marvel is the fact that there are multiple generations of heroes in the DC universe. I enjoy the fact that the JSA incorporates the old geezers - er, the older and wiser mentors like Green Lantern, Flash, and Wildcat alongside the 20-30-something heroes and finally the third generation of teen heroes. There's something oddly comforting to me about such a long history of heroics and the passing of the baton.
Although Marvel has many characters who were around during WWII (and before), there doesn't seem to be anything quite like the heritage that DC has. Although I suppose the presence of so many characters, often with the same names, could be confusing to some readers, I wouldn't call it a crisis or anything.
To some extent we see a "2nd generation" hero right now in Bucky Barnes as Captain America, although for long-time fans it wasn't handled in the same way DC generally handles the multi-generational thing. DC's advantage in this game is that they kept their heroes alive.
Marvel could have -- at the same time DC was resurrecting their Golden Age greats in the pages of All-Star comics (by Paul Levitz and Joe Staton, c. the late '70's) Marvel was bringing their same-era characters to the fore in the pages of the Invaders. But while DC chose to set All-Star in a contemporary continuity, Roy Thomas wanted the Invaders to be sort of an "untold tales of WWII" type of book. A boat missed, I guess.
I was recently re-reading Sub-Mariner #14, where Namor encounters the adult Toro (who mistakenly believes himself to be the original Human Torch). In my opinion, this was another boat missed. What would have been wrong with two Torches in the Marvel Universe? There would have been an infinite number of possibilities for them to coexist -- and without really ever having to cross paths.
And lastly... Tana, I see you've switched your avatar from Roy the Boy to Nefarious Neal! Keep 'em coming!!
Of course, there's an inherent problem with having a multi-generational universe: you have to deal with aging. DC has managed to side-step and trick their way out of this a few times, but the longer you go on, the more people are going to be questioning why (for example) these heroes who fought in WW II are still alive and hardy. The other thing is, the middle characters (like Batman for example) don't seem to age (perpetually 29 or so, according to old dictums) but their sidekicks grow up! They've allowed Green Arrow to age some, but now he's out of step with his contemporaries, like Batman or Green Lantern (although after Parallax I'm not sure we can know Hal's 'real' age).
It's a confusing aspect of this situation. But all in all I guess I still would rather have the multiple generations than not.
I tend to think of DC as having 3 and one half generations... let me try to explain.
First you have the golden age heroes.. mainly the JSA they even have thier own trinity Alan scott, jay garrick and Ted grant.. each even has a in Universe reason for still being alive.
Next we come to our silver age the Trinity supes, wondy and bats this then extends to GA, Barry and Hal i'd say these ppl are all in mid to late 30's.
Then we have thier sidekicks .. Dick grayson, wally west, donna troy, speedy ect. basically started to age in the 80's now all seem to be in thier mid 20's.
finally we have those sidekicks replacements and thier peer's Tim drake, conner kent, cassie, bart... all teenagers.
soo almost 4 generations and DC for the most part makes it work... Marvel does not.
Yes i know Bucky took over but really after WWII steve was maybe 24-25, soo buck would be 19... and marvel has tried for the kids to take over before.. the Mar-vell clan but does that really work as thier are clones/children.
they have the MC2 unverse where most of the silver age heroes have retired .. gone on to teaching roles or died but no one reads this universe its an alternate reality soo does it mean anything?
As i said DC does a great job with the legacy charas each generation has thier own version of a Trinity, 3 and 1/2 seems to be the limit tho and every 20+ years they have to re-boot thier universe.