cmwdjw - here is some suggestions on your 30k Delta miles:
1) You mention that you fly CO alot (and have miles with One-pass). Well, CO and DL are both partners of Air France. If you earn a few more miles in the DL program, you can get a free ticket on Air France with those miles. Do the same with the CO miles, and then 2 people can fly to Europe on Air France, one using DL miles, the other using CO miles.
2) You may be able to do the above scenario with other common partners as well. ie: if you have miles on UA, then one you could both fly on UA, one using United Mileage plus miles, the other SkyMiles. The same applies with Aer Lingus and a few other airlines that are partners with Delta and another US carrier. Since I don't know your mileage balance on other Freq. Flyer programs, I can't advise you here.