[Tool Agnostic]

I saw your fancy glue-ups in a different thread, and they look fairly uniform in nature. It won't start out perfectly flat on top, but it should be reasonably close. I think you can flatten them with your random orbital sander and a straightedge. Test the straightedge often, at all different angles. Don't hover over any one place. Most important: Remember that you must sand everything down to match the "valleys." You can't sand "up."

With all those crazy angles, a hand plane may be difficult, as the grain goes in different directions.