Congratulations on the new bike! Sounds fabulous
I have a Zefal bar-end mirror, which I quite like. I had one on my last bike, too. (same kind and model)
Make sure to loosen the laces over the front part of your foot and see if that takes care of the numbness problem before you start moving the cleat. Feet splay out with pedalling pressure and can swell with exercise, so check the shoe first. You can even take the laces out entirely, and relace them skipping the holes closest to your toes. I do this on the left shoe of my running shoes, and might on the left shoe of my biking shoes.
Have fun!
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson