I would watch an entire series based around on the misadventures of these two.
The novelty would wear off. It's all about quality, not quantity.
Isaac and Miria
Shizuo and Izaya
Why does this author make great side characters but boring main characters?
Theyre pretty one dimensional goofy characters. Theyre only good when theyre interacting with the more serious characters. I think it would get boring quite fast. Theyre supposed to be the spice not the meat and potatoes.