I am at Hall Of Fame level and there is a gold league, Greatest Of All Time Series. It costs 2K gold to enter, but the 1st and 2nd place finishes net you 6K and 1800 gold. Even 3rd place gets you back 1K gold.
Results have not been bad. I have six 1st place finshes, three 2nd place and one 3rd place. So, spending 20000 gold has gotten me back 42400. Now, I can make a move for some prime players, even legends.
Definitely worth a try, if you have a very good team (all 5-star players would help). And auto play will not help. Play each game yourself.