Brian, I like your shop. I already gutted your shop and redesigned it. Lol its not on paper but in my mind. You know how you said you like the cabinets I have. Well the back wall where your lumber is stacked up well you could start here. What you could do is hang all upper cabinets on a french cleat across the wall but keep the top of cabinets 12" down from the ceiling. Then you could lay a 1/2 plywood across the top. Now you have cabinet space for tools and a shelf all the way across for tools in a case. Like I have that corner shelf in my first picture. Then on the other wall with all your plywood. (I’ll get back to underneath the cabinets in a bit)
What id do (this is only suggestions) is put my lumber rack on this wall all the way up to the ceiling. Right where the garage door tracks are. Figure out what is the longest lenght wood you would use in a project. Then add a foot. So if your building cabinets and the longest piece is 5 ft then make your rack 6 foot long Or 7 foot. That way you could by 12’ or 14’ and cut them in half and stack. Your lumber should be close to the door. Pull up and unload with less walking. Looks like by the picture you have 16 to 18 inches from wall to the door opening so then next to the lumber rack put your plywood.
what I do here is build a large swing cacabinet to accept your sheetgoods but above it do a sheet good cutoff cabinet (open face).or do the alternative rack. See pictures

Now back to the wall with all the cabinets heres a bench system you could modify to swing up you tools

Other ideas

Hey you know we could always talk on the phone if you want any help just let me know. Like I said these are suggestions.

Jeff Vandenberg aka "Woodsconsin"