I like my rotary cutting table height. Just measured it, and it is 3.5" below my belly button. If I bend my arm at the elbow, it is at least 5" below that; I think any higher would make it more difficult to exert pressure when rotary cutting.
My table is 40" deep, which is way more than is necessary for rotary cutting. I always end up with plastic bins stored at the back end of the table (which is against a wall). I consider it a huge advantage to have a cutting table that is free-standing with access from all 4 sides; mine is in a corner, so I only have access to 2 sides. It still works great, but 3 sides would be better. Your proposal of 36" in depth is good.
My table is 70" wide, which again is more than is necessary. The extra width is nice when handling large pieces of fabric or bolts.
Aside from cutting, I use this table for machine quilting while standing up. My dh made me a styrofoam table that fits around my domestic sewing machine. I place both on my cutting table, and I have a large flat surface for machine quilting. Standing up while quilting means I can quilt much longer and do not develop the pain in my back and shoulders that I used to get when machine quilting while sitting down.