Dan --
Sounds like a great setup. I like to have a set of lights that has motorists scratching their heads and saying, "What kind of aircraft is trying to land on the road ahead?" and sounds like you've got it.
The MR-16's put out a lot more light than the MR-11's because they have bigger reflectors. The best thing you can do to increase efficiency is to have a big reflector.
Do you have a link for the clearance lights?