When you say it's a robot on the phone, and you're looking for a human, is that meant to be taken literally or figuratively? Do you actually get a human, who you feel is acting like a robot and giving you standardized lines?
I could take a whack at your questions, but keep in mind, your questions wouldn't be under the department that I worked for. I only dealt with cases and transaction disputes. And, it's been nearly two years since I've worked at eBay. But with that in mind, I'll try and share my thoughts.
With your first question, to be honest, I have no idea. I don't know how ANY of that works. All I know is that you're right, as a top rated seller, your listings SHOULD be at the very top. For what it's worth, if I got your call, I'd ask my boss and if they didn't know, I'd happily get you to the right department (and yes, there is a department that would specialize in questions like that).
With your second question, the only thing I could think of is that your auctions might not be set up for international shipping. If you don't allow international shipping (as in, when you list the item, you don't select the option that says you'll ship internationally), then people outside your own country won't even see your auction. If it's only a few buyers in those particular countries, though, and you're able to make sales to some international buyers...then I really don't know.