Yep, you're right - there's a fine balance here as I ended up with 10M gold at the end of the game.
I was ultra-cheap, though, and didn't use much Blackie Teleportation until the end of the game (although you'd probably only spend 50-100k from all the teleports). I guess I had some nostalgia for the sailing days!
I was really raking the gold in in Helvedia (and experience, too) as it seemed like some battles were almost 100k a pop.
I think if you go the Dragon Rider route, you have to ensure that you don't lose any - 100k a pop is too expensive to lose one.
Pretty much most other losses can be handled by Recruiter or Puppeteer if you do it right.
/C\/C\