Well you've already answered a bit of that already, but I still wonder : why did you take The Jungle Book as a basis for the series? How did you get such a crazy idea? ^^
I mean, the stories are very different (more adventure/emotions than a musical), the settings are very different too ("human-like" world, civilized, characters standing on 2-feet, etc...), and the final result looks more like a parody of the Jungle Book than a spin-off!
And yet, it turned out to be a perfectly coherent and interesting series :)
It seems like a very strange choice (and now that I've watched it, I have to admit that Baloo fits TaleSpin even better than he did for The Jungle Book, especially since you re-worked the character and added much more depth to it)
Well ok, this is more a statement than a question ;)
We never intentionally thought of TS as a "spin-off" or even a parody of Jungle Book. As I mentioned, we were in a time crunch to create a new series. We know Baloo was a great character (from the B Players development) and we weld that onto the Launchpad McQuack air delivery service idea from Duck Tales. Those were the roots of the series.
Kit came next, because the dynamic of the eager son (Mowgli) and the bad role model father (Baloo) was so clearly delineated in Jungle Book. Next came the Cheers angle with Rebecca as inexperienced boss and surrogate mother for Kit. Wildcat was based on the drugged out pilot character from "Fandago" (go rent it). Only after these elements were in place that we decided to add a neutral territory (like Rick's Cafe American from Casablanca) and who better to run it than King Louie??! Shere Khan was added even later. So as you can see, we didn't start off with a Jungle Book take-off... it was strictly the Baloo father figure/ lazy con man that we were interested in.
Sadly, Jungle Book is such a seminal film to so many animators of that time that we had trouble hiring some people because they thought we were ruining the original concept. Perhaps we were, but I've had artists tell me later that they wished they could have worked on Tale Spin after all.