I've seen some rigs that are absolutely mind boggling with their complexity, but your UI adheres to the K.I.S.S principle - Keep It Super Simple (although it may not have felt like it when you were putting it together). But now at the end of the day you have a rig that will serve your purpose and can be adapted to any future character you create. Very nice job!

Only thing left to ask is – How much & where can I get a copy

Dave.

PS: COU(walk cycle)GH