You look at Kids' WB over the years, and you'll see it's always been about action and revivals, though comedic shows did have a place on the lineup.
You had a revival of Sylvester and Tweety and comedic action in the form of Freakazoid! and Earthworm Jim in year one. You had a revival of Superman a year later and comedic action in the form of Road Rovers the following year.
Over the duration of the block, Kids' WB had three versions of Batman, new versions of X-Men and Spider-Man, other revisions of the Superman mythos on Legion of Super Heroes and Krypto the Superdog, two revisions of Scooby-Doo, and a terrible revision of the Looney Tunes characters with Loonatics Unleashed.
Action also had a place on the block, whether it had staying power like Pokemon, Yu-Gi-Oh!, Men in Black, Static Shock, Jackie Chan Adventures, and Xiaolin Showdown, or short-lived like Card Captors, Calamity Jane, Brats of the Lost Nebula, The Mummy, The Zeta Project, Cubix, and the ill-fated Toonami block on Kids' WB.
The success of Pokemon seemed to have blinded the management of The WB to develop fewer pure comedic programs. The ones that seemed to have succeeded were those inspired by the classic Looney Tunes mold of shorts (Animaniacs and Pinky and the Brain stick out) and the comedic adventure shows like Mucha Lucha. The shows that seemed to have a youth-oriented cast like Detention, Waynehead, The Nightmare Room, and Generation O! (Johnny Test is the very rare exception) as well as shows that were supposed to educational like Channel Umptee-3 and Histeria (sadly, it was a well-written and performed show from the minds behind Animaniacs but didn't really click with the viewers) and truly moronic shows like Coconut Fred didn't last long nor found success on the block.
The last big show on Kids' WB is Tom and Jerry Tales. Why? Because it brought the block full circle. It's a revival comedic series based on a classic animation duo in shorts-form having wacky misadventures. No searching for Sanrioesque creatures for battle. No grown folks in spandex suits with superpowers. No snarky kids making crude comments. It was genius. The last great show of Kids' WB.
Had the powers that be continued with the block, I believe they would have returned in that direction. They would have brought back Tom and Jerry Tales for another season and explore what they could do with their other library characters, particularly the Hanna-Barbera (aside from Scooby-Doo)and Looney Tunes characters in their traditional environment.
They had a minor success with Bah! Humduck a few years ago, and it would have been interesting if they considered bringing those characters back in their traditional, unaltered forms. There's a bit of revivalism in the Hanna-Barbera characters market thanks to the recent McFarlane Toys sets, the Hanna-Barbera Super Adventures comics, and the recent DVD releases, so it wouldn't have been surprising that Warner Bros. would have been preparing to revive those characters in some capacity. The announcement of T-Works (now Kids' WB!) made it a priority that Looney Tunes and Hanna-Barbera characters would be a prominent part of the site, and they are. The whole Mashup! concept they introduced at the site, which crossed over characters from separate brands and studios, could be one step in creating new programming featuring those characters.
In fact, many of Warner Bros' current productions ARE revivals of older properties. Whether its based on comic franchises (see the DC Universe animated movies and the upcoming Plastic-Man series on Kids' WB dot com), popular franchises (see Tom and Jerry and Scooby-Doo DTV movies and the upcoming Wizard of Oz series on Kids' WB dot com), or titles being developed as feature films (it's not that unfantomable to see a new animated versions of Jonny Quest [like the early 90s Flintstones movies, Warner Bros. is pretending Real Adventures never existed], Thundercats, and The Jetsons to tie in with the theatrical versions), Warner Bros. are developing new projects based on older properties. Some are known, most are not.
If Kids' WB did continue on-air, I would not be surprised if they continued the whole "action shows and revivals" mode they've been doing for quite a while now.
I still hope they reconsider totally dismantling the brand on-air. Kids' WB would be a fine digital subchannel for The CW.