Now what a funny coincidence, I too was marathoning the entire DVD rip for the last few days.
Since Madoka Magica, I've been digging up on Shaft's previous work, particularly Shinbo. I've already had experience with Shinbo's unique artistic directing style after 2 seasons of Maria Holic, so I knew what to expect.
Before Bakemonogatari, I started with all 3 seasons of Hidamari Sketch, since it's Aoki Ume, the character designer for MadoMagi. I can totally envision Shaft doing a cheerful MadoMagi spinoff in Hidamari Sketch style. Even Shinbo himself said so.
Though I get the feeling Shinbo isn't that in charge of Hidamari Sketch that much, as there is less of the "annoying" text narrative so prevalent in Maria Holic and Bakemonogatari (i.e. forcing the viewer to pause and move forward slowly in order to read those rapidly changing walls of texts on the screen).
I'm not sure whether to bother with Zetsubou Sensei, as I hear it's pretty much Shinbo on crack.
(Since I don't follow the Negima manga, I think I'll pass on Shinbo's Negima version as well)
Concerning the cast, Saitou Chiwa is dazzling, so was Hocchan and Sawashiro Miyuki.
However, there is just one request I ask of Shaft.
Do not let Hirano Aya anywhere near the recording studio. AFAIK, though Shinobu never talks for the whole TV series, I believe she speaks (in character, like the other seiyuus) in the DVD commentary. But due to Hirano's off-screen antics, I must confess that I now find it very difficult to imagine Shinobu speaking with her voice again. I don't care if Shaft have to pay a hefty fine for firing her and replacing her with someone else. But just no, not Hirano.
Reason is off-topic, so it's in spoiler tags to save space
Anyway, back to the topic. I love it.
After watching it, I can understand why Shaft fans rate this higher than MadoMagi, though MadoMagi has the advantage of being an original work, while Bakemonogatari relies on Nishio's storytelling as a benchmark.
Conclusion: To truly appreciate Shinbo, always wait for the DVD. I'm glad I waited this long just to watch this whole damn thing.