This thread is a response to the recent thread on the chromatic side of our treasured cyber home.
Whenever I go on a bit about harmonicas (which happens daily, don't get me started), I posit that the diatonic is perfect in first position for nursery rhymes and Christmas carols (and the blues in second position).
For those of you who play both, there might be advantages to using a chromatic--the occasional accidental--but mostly the holiday tunes are diatonic.
And of course, the little guy makes a great stocking stuffer (and is the gateway instrument to our big guy).
Jingle Bells, anyone?