As you can see below, my EUA record is pretty darned good for a lowly Silver (although I generally fly on Tues. or Weds. and things are pretty dead then). If you want to maximize your EUA opportunities, my suggestion would be to avoid "busy time" flights originating from hub cities (which others have covered), take red-eyes coming back east if you're going to the coast, and fly into and out of slightly less popular airports (e.g. SJC instead of OAK or SFO) .

Also, avoid NS transcons (unless your schedule demands it). Also, when booking through CO.com, try using ZFV as your origin. Sometimes you can find better fares than out of PHL (sometimes). BWI can also yield some rather ripe fares.

I would say get KVS to check R bucket availability, but the R bucket is no longer where will EUAs come from come Sept. 20th. As most CO FT'ers know, the R bucket is being displaced with the F bucket which none of the GDS' can display (at least yet [hopefully]). But you can look at data for R bucket availability for flights up to Sept. 20th and still get a general sense of availabilities. Just look when the windows kick in. All that can be found on the CO website. Well, that's about it. Have fun and good luck.