At the outset, I must confess that I have always been partial to the Lyric Opera of Chicago’s grand-scale productions of classic Broadway musicals.Whether it’s “Carousel,” “Oklahoma” or “Sound of Music,” I have always looked forward to enjoying the new delights that these huge extravaganzas bring with them, including Lyric’s current take on Lerner and Loewe’s “My Fair Lady.” It did not disappoint.What’s not to like? The gorgeous symphonic tones …