The only other possible way is search by schedule - select 50 and see if you can find an "interesting" route for straight forward return.

have just looked and - AUS-FRA-AUS brings back

AUS- dfw/dfw+ord/dfw+lhr/lax+ord - FRA and return
FRA - ord/dfw/ord+dfw/ord+lax - FRA

so you can do via LAX both directions

which would yield a few more miles