I can't vote, but renting them out seems like a smart move if they aren't played. Why just hold them while they can make money in the rental market? If the deck is played, just keep the key cards, and make a nice selection of interesting cards in the rental market.
My experience is that the market has dropped very very hard, but I don't own a deck with that kind of value. Either way, if cards are unplayed I'd advise you to rent them out for sure to get some returns.
Good luck making the decision :)