For all the talk you've made about stereotyping on this series, you've conveniently forgotten about Hadji. At the time it was rare for any Arab character to be portrayed in a positive light rather than a derogatory light. But Hadji was a positive character, even bringing some special skills to the others. As for what you say about the villians being portrayed in a stereotypical light, they weren't. I can see why you and perhaps others think they were, but I think otherwise because the villians were always that country's "locals". In other words, the villians in Egypt were never from Canada, the villians from Japan were never from Mexico, etc. In Egypt, the villians were always Egyptians, in Japan the villians were always Japanese, etc. But if you're concerned that younger children might see it the way you do and pick up on it, the best thing to do is to watch with younger children and then talk to them about it.
Jonny is only 11 or 12 and can't be on his own full-time yet. That's why Race Bannon comes along to help Dr. Benton Quest, Jonny's father.
The various locations are interesting. Even the violence is rather tame compared to what's in many of today's cartoons. A fine choice for kids who know fantasy from reality but aren't yet ready for stronger action-adventure movies or cartoons or other such tv shows.