TL, over the course of time, stock returns have averaged 10% over every ten year period since the 1920s, no matter how you slice 'em. 10% is a reasonable long-term rate. It is not reasonable for short term, especially today.
There are two schools of thought for paying off debt: One goes by ascending loan amounts, and the other goes by descending interest rates.
Personally, I belong to the descending interest rate club. Pay off the highest rate first, and work your way down. That 1% student loan? It would be out there for a long time in my book...
I do have one exception, and that ties into the logic behind the ascending loan ammount approach. See, every time you pay something off, you get a psychological boost. So pay off the smallest debt first, get the boost, and then add that money (what you were paying) to the payment for the next smallest. Dave Ramsey refers to it as a debt snowball, and as you keep going, it keeps getting bigger and bigger, taking out debt in larger and larger chunks.
My exception is that if I have a debt close to being paid off, I will pay it off, even if it's not next on the list. I'll take the short-term ego-stroking of knocking another one off.
Apparently, many people can't handle the apparently slow turnaround for the descending rate club, and they tend to give up before they hammer it out. For those folks, the ascending amount club is better.
As for keeping your emergency fund on a 5k credit card limit, my only concern would be that when you need it, you may not be in a good position to take on another 5k of debt. I believe it's easier to have the money sitting around and draw on it (and then replenish it) when needed.
Whew! Weighty stuff, but important, in a lot of ways. Neither of my parents is comfortably set for retirement, and I really want to be... long before I get to retirement, too.