Q2: Can I weight certain links to appear more often?

Yes! To weight links, simply add them multiple times:

@links = (
    "http://priority.com|Priority Site",   # appears 3x
    "http://priority.com|Priority Site",
    "http://priority.com|Priority Site",
    "http://normal.com|Normal Site",       # appears 1x
);

In this example, the priority site has a 75% chance of being selected.

Or use weighted format with a number:

@links = (
    "http://priority.com|Priority Site|3",  # weight 3
    "http://normal.com|Normal Site|1"       # weight 1
);