The entire cast, but I would like to mention Elan - Elan, who manages to maintain being The Nice Guy, even after taking a level in Badass and after having gone through several rounds of Break the Cutie, he's now a resilient, more solemn, but still basically Nice Guy who can still be amazing comic relief.
Xykon is perhaps the only villain I actually fear...and he's still freakin' hilarious.
Oggie, Dimo and Maxim. All the Jägermonsters are awesome, but these three who join up with Agatha really take the cake. They transition seamlessly from comic relief to pure badass and back again as the situation warrants.
I would like to nominate the entire freaking cast as being full of awesome. Even one-shot characters like the girl with the teddy bear.
And owning the best hat in the history of existence.
You forgot Jenka. First female Jaeger introduced, sets a town on fire, bosses Da Boyz around effortlessly, and Gil/Agatha shipper? Yes.
The whole crowd's for it. But Jenka rides a bear. This counts too.
Ardsley Wooster is more subtly awesome on analysis. Even before he backhands the resident Axe Crazy while she has a gun on him, he manages to read the situation before the rest of Agatha's party even NOTICES it, disappear, punch out a Wulfenbach soldier, take his gun and sniper perch and start shooting. Later, while Boris has to beat the location of the Jaegergenerals out of a Jaeger (itself a Crowning Moment of Awesome for him) Wooster finds it on his own, from the outside, and make a dramatic entrance and exit (after destabilizing the Wulfenbach-Jaeger alliance) from the outside of an airship. Nobody does it better, indeed.
Red Mage too, for his tabletop gaming shenanigans. The man broke Time and Space and put it back together.
The Black Mage is the only real sympathetic guy of them all. OK, Fighter -could- be so sympathetic, but he's usually too stupid to be hurt, so there's no reason to feel bad for him. Thief is a better-than-thou racist (or perhaps specieist), and Red Mage is just plain weird. But who on earth cannot symptathise with Black Mage's noble and admirable goal of destroying everything? I mean, is there anything wrong with that? OK, so maybe it is, but if the universe is going to be destroyed, then I'd much rather have Black Mage do it than anyone else. He's my hero and guiding light on an otherwise desolate planet.
Anytime Fighter and Thief interact with each other. It's not terribly often, but you'll get a gem every single time.
Sarda, almighty Wizard That Did It, knower of everything that has ever happened and ever will happen, older than time itself (by his own doing), and most importantly: a complete asshole. He has all the power in the universe and he focuses 100% of it on fucking with four guys who totally deserve it.
Bikke. Recall that Sarda is omnipotent and can see through time. Now understand how crazy it is that Bikke took him completly by surprise. Hell, even Sarda himself was impressed by that.
Oddly enough, I have a special place in my heart for Shortpacked!'s lovable jerk Mike. Sure he's a total asshole, but Mike is also not afraid to point out the huge personality flaws in people that are otherwise blissfully unaware of them. Also, he banged your mom. In the ass.
Richard. Just as psychotic as Belkar and Black Mage, but he manages to pull it off with such style.
Largo: I see a booze machine. Give me some quarters
EVERY FRAKIN' CHARACTER from Hanna Is Not a Boy's Name, the absolute winning position going to Hanna himself for being the cutest redheaded ball of klutzy energy ever.
Most of the main cast from El Goonish Shive! Special mention for Susan, who started to lose her idealism as a child, had all sorts of horrible things happen to her since (her parents divorcing, being called upon to kill a vampire, learning that there were other people who could have and should have been the ones to kill said vampire, being ignored and ridiculed by most of the school) and she still stands by her beliefs and does what she thinks is right. It also pleases me to no end that she started out as a Straw Feminist and was developed into such an awesome character.
Too many Homestuck characters to name. Even bit part players like AR and Nepeta get their share of characterization in this comic, and every single one of them has legions of fans somewhere on the expanse of the internet.
No mention for Kanaya the Vampire Fashion Queen yet? I'm surprised, considering she only got shot through the torso by Eridan, then later on right before the mega-awesome three-way showdown is about to go down, she comes out of fucking nowhereglowing andfucking tied back together with a piece of cloth, to kick Gamzee in the nuts, punch Vriska in the face, and then slices Eridan in half after breaking his wand he worked so hard to get. And then she retracts her chainsaw into lipstick form and puts on lipstick the same color as her blood, which is still spattered with Eridan's. Then she licks her lips like it's no big deal. No wonder Vriska just stared at her with this little "<333333333" expression. And that's nine threes, not eight. Pretty big fuckin' deal for the eight-obsessed Vriska.
Ash from Misfile. He is the only character I've ever seen to get gender bent and have it notPlayed for Laughs. Ash is a mega-Woobie, acting like a real transgender teenager would, feeling trapped in his own body. Those of us in the LGBTQ community definitely appreciate it.
Jamie and Erin from Girls with Slingshots are so freaking adorable I can't even stand it. Every time I see them together in a new strip, even if they're not its main focus, I can't help but squee.
Florence from Freefall.She's very smart and funny. She deals with Sam and Helix very well given the circumstances, and actually remains sane when she found out that Helix thinks you can cook with explosions. She also manages to get herself in and out of trouble quite a lot on her own.
How about Allie? Or Simple Dog? Or for that matter any character from the comic at all?