It´s really hard to come up with 52 titles! If Marvel were to relaunch their titles, I would suggest something along these lines...
SPIDER-MAN
1.The Amazing Spider-Man - Bring back John Romita Jr!!
2.Peter Parker, the Spectacular Spider-Man - A monthly companion to our original comic
3. Spider Woman - Bendis did a good job with this, could Alex Maleev be far behind?
AVENGERS
4.Captain America - Only if Brubaker writes it!
5.The Invincible Iron Man - Actual creative team could do a monster revamp! I have faith in them
6.The Incredible Hulk - Burn down the house (all seventeen hulks) and just keep it simple, stupid. Banner + Jolly Green Guy = HULK
7.The Mighty Thor = Less focus on Asgard on a while would be nice
8.Hawkeye = Considering he´s going to be in the next movie, an ongoing series would be nice
9.The Mighty Avengers - Just one team. Not Secret, not classic, not New...no Wolverine, no Spider-Man. Too much to ask?
10.West Coast Avengers - I really loved this comic back in the 80's. Why not?
11.Avengers Academy - One of the best comics out there, this has to stay.
DEFENDERS
12.Doctor Strange - One of the flagstone characters of Marvel, why do I dream of Sienkewickz drawing this?
13.Strange Tales - Telling the tales no other monthly can tell...
14.Namor, the Sub-Mariner - Jae Lee, a good writer. Need I say more?
15.The Defenders - Could they get the revamp they have been waiting for? (the last good version I read was on "Twisted Toyfare Theater")
16.Silver Surfer - Cosmic drama queen needs a remake. Surfer 2.0.
SHADOWLAND
17.Daredevil - Keep the actual team, they have a good feel for the character.
18.Heroes for Hire - Interesting concept, change the artist.
19.Luke Cage: Power Man - This character is overdue for his own comic, specially if you get him out of the Avengers.
20.Iron Fist & the Seven Warriors - One of the nicest comics in the last years was the Iron Fist Saga, bring him back!
21.Punisher - As long as you dont cut him up in pieces, transform him into Frankenstein, he´ll be fine.
22.Moon Knight - Great character!
23.Black Panther - Take him back to Africa. Give him a good creative team, make him look like the one in "The Avengers" cartoon series. Cool.
X-MEN (Do we really need so many X-titles out every month?)
24.Uncanny X-Men: The base team (Cyclops, Nightcrawler, Collossus, Phoenix, etc)
25.X-Men Legacy - A "b" team located in another city, hopefully led by Storm
26.X-Force - This comic has a great concept going
27.New Mutants - They would have a chance to make them young and fun again.
28.Wolverine - JUST - ONE - TITLE!!
29.X-Men: First Class - This was a great concept, how could it not work?
30.Magneto & the New Generation - Magneto opens up his own school of mutants. Not?
FANTASTIC
31.Fantastic Four - Bring back Johhny Storm. We all know his death was a gimmick.
32.Ben Grimm: The Thing - Could he hold a monthly title again, like he did in the 80´s?
33.Savage She-Hulk - Very underrated and underused character, once belonged to the FF
OTHERS
34.Deadpool - Excellent character, could I dream of Liefield again?
35.Deadpool & Cable - Why isnt Cable in the mainstream?
36.Elektra - a monthly gig for the sexiest assasain? Who wouldnt buy that?
37.Marvel Team-Up - Change the name if you wish, dont make it all about Spidey, there are a lot of cool team-ups to happen in the MU
38.Hercules - His monthly actual is showing that Bob Layton wasnt crazy to trust this character back in the 80´s
39.Nick Fury, Agent of Shield - Has a lot going on for him right now
40.Ka-Zar & the Savage Land - Could someone get this title RIGHT for once?
41.Man-Thing - As long as its better than the 2005 movie
42.Blade the Vampire Hunter - Vampires are the coolest thing today, and Marvel isnt publishing its only original vampire? Weep, Wesley Snipes!
43.Excalibur - Call 911 - Alan Davis could help
44.Captain Britain & MI-13 - I loved this series! Why did they cancel it?
45.Spider-Girl - Just change Ron Frenz and I´ll buy it
46.Marvel Classics - Stories from who knows when and who knows why
47.What The?! - Come on...You dont miss this one too?
48.What if? - Monthly pressure to make this happen...Hmmm...maybe this one is not meant to happen
ULTIMATE LINE
49.Ultimate Spider-Man
50.Ultimate Avengers
51.Ultimate X-Men
52.The Ultimates