Yeah, I just remembered the Decade AU of Kabuto made Tendo's character a lot more likeable in that version. Mostly by merging Juka and Hiyori into a single character (making his deal with her secret make more sense, as they still grew up together), and by having him in general be much less massively dickish and selfish. I really want to see the series that was from instead. (Seriously, I like your theory that Kabuto is the self-insertion/possession sue version of a better series. It really does read like bad fanfiction in how messed up the morality can get.)

The other amusing note is the episode indirectly credits this to Tendo's parents surviving and raising both of them (teaching Tendo something vaguely approximating empathy and humbleness). Juka's a lot less eccentric/irritating too in that universe - I'm wondering exactly how Tendo's grandmother screwed them both up so badly...