From my perspective the higher the rating the higher the payouts.
End of season has some issues with rentals being called back(canceled) by the owner to get the 3x increase in rental income on the last day.

I generally rent enough to get the daily quest rewards and stay in my current league. Try to keep your rental expenses less than your average daily wins. 50 to 70% to keep your account growing and to build in a buffer for when you get unlucky and lose most of you matches.

Get some experience playing because the bots in the bronze level play the ideal setup for the mana level of the match.
You can check out splintertools.io to see what percent chance you had to win the match. Then substitute in other cards to see if the percent increases.
https://splintertools.io/