First of all, thanks for making splinterlands playable for large collectors!
My input would be that the quick deck rentals option sounds like a great time saver, probably more useful than the rental bids option.
On ARPA, I would say only chaos forward is likely worth the effort. Untamed and earlier have decent land boosts, so a lot of those cards are likely to not be on the rental market, and it would be really difficult to have enough data to auto price efficiently.