Hello, Life!
"loads" are seat availability on flights
I don't know what privileges you have w/USAir.
For us it's all partners, different ways to travel.
We all get some sort of Industry Discount, varying rates--like ID90 or ID95 or 96 etc.
That means you can "buy" standby requests for seats on different carriers--like we can fly Delta to Atlanta (free) then Panama City, Panama for taxes and fees. We can switch to Copa Air to fly to other cities in South America (in our case, Manaus Brasil) by going to our tkt office and buying ID90 (90% discount off base fare) tickets plus fees/taxes. They're refundable, so it's better to buy what you need to take a trip overseas, because there aren't always Delta tkt offices that can do this!
We don't pay for Comair since we own them; commuter line ASA is free, but we have lower priority and same for them on Delta. We pay small fee for Air France but we all hate flying thru CDG airport--MON DIEU!!! It's good or BAD....

So, it's just alot of "work" to get it straight! You should have pass bureau/website to answer darn near any question. I'm sure fellow USAir emps will give you the skinny soon.
Domestic first class is nearly impossible w/out high seniority. All those miles members get upgrades--maybe on intl rtes?
You have my sympathy t have 3 kids at those ages!! Just kidding (no, I'm not!!) but they'll be fun to travel with once you smack their ipods out of their ears while going thru immigration and security! Trust me--just have them put them away until they're allowed on the aircraft--it's easier! Phones--ACK--tell them they can't get ANY coverage--not even texting--where you're going.
Plan A B C--well--don't try to go anywhere you don't at least have B in the works. Have you seen prices for flights these days?? Non-rev just means you really aren't buying a tkt--just a prayer for a seat!
How's that--did it help?