I've seen pictures where people have stuck big lego sheets onto a wall and/or table with drawers for all the lego under.

I've thought about adding a ledge shelf around my son's room for the Lego Creations. Go to a Lego store and figure out the width. I got my son clear trays so he could pour out his Lego and paw around for the right piece then pour it back in the box, but he doesn't use the system.

My son was a Lego addict also. He took over our dining room for about three years! If I had the luxury of designing a dedicated space, I would do a large square table in the middle of the room with a chair on each side, so that everyone has his own space. In the middle, I would keep sorting bins so that they can more or less keep different sized pieces separate. I know how complicated this all gets, especially when you are buying kits that have specialized pieces. I bought my sorting bins from Home Depot, or someplace like that. They were the type of bins that you would use in a workshop to sort screws and nuts and bolts, etc. use different sizes based on the size of the "parts" you are organizing. Beyond that, some low Ikea shelves along a couple of the walls for displaying on the top, and more storage below is all you need. Oh, and a broom and dust pan for sweeping up all the pieces that land on the floor!

What about the peg boards with containers on them? They hold different size containers, you can move them around sort into groups etc? Probably at your hardware store?

You can create a Lego wall by painting blocks in lego shades, and adding slices of foam noodles. For a focal wall, you might also try covering an attached board (for removal later) covered in one color of legos, so that building can happen on the wall, itself
Ikea units can be colour coordinated and added for display and storage. Loose pieces can be corralled in colour coordinated baskets.