Rental income for CL is low and probably going to be lower once the Airdrop ends and those who were holding open their packs flooding the market. Love the analysis but I think Rewards Cards would yield better value/return. Then supplementing with CL cards. I'm buying only the cards I plan to use/play with currently. If you think about it, there's barely over 20% CL cards circulating. Get rewards cards that will have increased value once Wild/Modern split happens.
You are totally right, rental income for CL is low. But, I was playing Silver I league and earning nearly 100-200 Dec daily so I decided to rent out all my cards. Today ( 2. day of the season ) I earn 350-400 Dec/Day with my 1.700 USD valued cards. At the end of the season, this figure rises up to 2000 DEC or more.
it's not much, but the daily rental income seems more profitable than playing games, as there are not many good cards coming out of the daily prize chests.
I buy cards with daily rental income and prepare for the next game modes.