Vertical storage for lumber was a big solution for me. Not only can I stack more, but I don't have to worry about the loads on the wall so much. (There is still a lateral force on the wall, but most of the mass is resting on the floor.) And if you stack it right, you don't have to worry about the wood bending. I use a 2x4s lagged into studs with 1-1/4" dia. dowels friction fit into holes drilled at about
5-1/4" o.c. (to miss the lags into studs at 16"o.c.). These aren't glued so I can move them around as needed.Also, take a walk through your local home improvement for ideas.