I make greeting cards by glueing RC prints on notepaper which I have pre-printed with my contact info on the back. In my experience two things happen to my cards. They get put on the mantle or shelf or kitchen counter so they can be looked at by everyone who comes in the house or the recipient goes to a local joblot type discount place and buys a little frame and puts the card in it and stands it on the desk or mantle or counter or hangs it on the wall somewhere. For a card to stand up on the mantle or shelf it has to be pretty solid stock. It has to not collapse in serious humidity. So I use a recycled paper stock which is quite heavy, but a much lighter weight matching envelope. The paper is the weight of a wedding invitation. HTH
