Agree with this proposal. Switching the rental system so that cards on cooldown can't be posted for rent is a good short-term fix. It is more frustrating to pay money for a card only to not be able to use it than it is to not be able to list a card. Paying money for a card on cooldown could easily cause some to never trust the rental system again. Ideally those trying to list cards for rent would get a clear UI indication that the card is on cooldown and that it cannot be listed for rent until it is off cooldown.
RE: SPS Proposal: Make it Cool for Rookies