Despite the fact that I read nearly all of the Ultimates titles, and have for a long while (heck, I even bought ULTIMATE ADVENTURES and actually liked it, although I didn't bother with ULTIMATE ELEKTRA and only have a handful of ULTIMATE MARVEL TEAM-UP issues), pinning down a "favorite" is a hard thing to do right now.
If you'd asked me this last year, the easy answer would have been ULTIMATE X-MEN, which Vaughan was jazzing up with a great writing stint. His 19 issues and Annual got me to like UXM in a way that I hadn't in years (since Millar left). But now he's gone and Kirkman's run is still decent, although inferior to BKV's, especially since Kirkman's main focus is pimping out his "Mary Sue" character so far, probably so we may care when he "goes evil" in the next arc or something. So I don't like this book as much as I did in '05, although I still like it.
Then there's ULTIMATE SPIDER-MAN, which I read via trade for years until after the WARRIORS arc, where I decided to hop onto buying it monthly with SILVER SABLE. I guess I can agree that USM's not as good as it was before CARNAGE basically, as some of the villians haven't passed muster (or even been Spider-Man villians). The thing that really holds this book back from greatness is Bendis' insistance on repeating himself to the point where I can predict maybe 50% of an arc before the first issue is in the can, and be 75% accurate. Its a shame because this book gets so many of the "Spidey fundamentals" right, especially since 616 Spider-books have all but abandoned it so Spider-Man could grow claws, eat people's faces and then unmask himself on TV. But its Bendis' insistance on remaining "inside the box" of his own creation that keeps this book on "predictable spin-cycle" and holds it back from true greatness. We know this "spin cycle". In every story, Spider-Man is a helpless feeb. He never wins against anyone who has boobs, and is running 50% against other opponents. Half the time, he needs to be rescued. And he is almost always unmasked, or fights someone who knows his identity, to the point where you wonder why he has a secret ID at all. He makes the same mistakes in issue #97 that he made in issue #7, and that makes all his stories and adventures feel like wastes of time when the hero himself never learns. Plus, the fact that Bendis seems to like having "Marvel Team Up" stories immediately after some shocking tragic story just sucks all the "oomph" out of the tragedy. While a team up with the X-Men makes some sense if Peter's dating Kitty (a great plot point, and DEADPOOL at least had a lot of great action and an almost competant Spidey), USM is pretty much Eric Foreman from THAT 70'S SHOW in a costume: a helpless "weenie-man" in a mask who needs to be perennially saved by his girlfriends. If any title needed a co-writer to infuse some LIFE from the spin-cycle, its USM. As it is, its enjoyable, if always predictable, B- overall level fare (with some stories being better and some worse, but B- would be the average). If Bendis would only abandon the idea that "flaws" are worth repeating, then it would be an A+ book, easy. And its the only title where Bendis actively CREATES something, from updated villians to relationships to whatnot, whereas in most of his other work, he relies on destruction. Marvel's damned happy at having one creative team on board for 100+ issues, but for god's sakes, I don't think I can take the spin cycle much longer. Bagley's art is fine, but Bendy really needs a co-writer to inject some new ideas and a storyline that I would actually be kept guessing by, rather than assuming "insert threat that unmaskes, humiliates Spidey that Spidey doesn't actually defeat", and be right 95% of the time. Its this insistance on "spin" that gives folks who are all for "anything that is shocking" more ammo.
ULTIMATE FANTASTIC FOUR is also a mixed bag. Launched by Bendis/Millar (Bendy did the dialogue, Millar wrote the pages where crap actually HAPPENED within a single issue), it lulled into enertaining mediocrity when Ellis came on board and tried to compete with Bendis in the "decompression" biz. Then Millar can onboard and juiced this title up like nobody imagined. It has his trademark action and wit, as well as imagination, but he's not as extreme as he is in ULTIMATES or WANTED, and the effect is all the better. I'll miss him when he goes, because he's really jazzed the HELL out of this book.
And then there's ULTIMATES. In a universe as "modernist" and cynical as Ultimate is, a concept like the Avengers is hard to pull off. The original ULTIMATES run had high octane action, character drama and an insistance on pop-culture references that even 2 years later seem outdated. But then came ULTIMATES 2, and Election 2004. And all of a sudden ULTIMATES 2 became a pamphlet for either an Al-Queda Recruiting Center or an Extreme Leftist Radio Station, because its anti-American zeal became to get more and more obvious until midway through when it all but overwhelmed a story where the Ultimates actually fight real "supervillians". Now we're in the home stretch and Millar's relying on the action again, which is always his strong-suit on Ultimates, and pretending that he didn't just preach on about how Evil America is, was, and always shall be for nearly 10 issues straight. It is for that that I call ULTIMATES 2, "America is Evil: The Series". Millar's insistance on "macho tough guy, Hollywood threat-esque finales" has also been repeated a lot. Hitch's art also makes it late as all hell, with it even being late if it was a bimonthly. I love the action and the art, but every issue of U2 makes me feel like putting a gun in my mouth and pulling the trigger because I don't believe that all of the world's problems begin and end with America, because that's just a cheap cop-out of a much larger issue. And I'm not even a Republican.
So I guess right now ULTIMATE FANTASTIC FOUR would be my favorite, but it varies from year to year, and arc to arc.
BTW, all of Ultimate's "event" crossover storylines have never overcome the extreme hype. ULTIMATE SIX was the best one, and even that was overrated. Ultimate does best when it sticks with a handful of unique yet interconnected titles, sort of like what Marvel used to do well.