Planning my next trip and would like to travel on Biz or first class from LAX-CPT-KTM-LAX or in reverse direction.

Which Frequent flier redemption would be best? (meaning best availability for November, December or January) I have enough miles for U.S. Airways, Delta, and United for round trip and AA for one way.

Also have some Avios points in case I need to do short segment on this.

TIA