Just a note that a "conventional" Star Alliance business class RTW allowing 26,000 miles over a year carries a base price ex-BUD of US$4872; bumping the mileage to 29,000 adds around $250 to the base price. A Oneworld Explorer 4-continent business class RTW ex-BUD has a base price of US$5401 and no mileage restrictions.
Sample 26,000 mile Star route -
Possible Oneworld DONE4 route -