Whimsically perhaps writing to Charlie - rambling, flamboyant in style (10)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

R (perhaps writing = whimsically, one of the “three Rs”) + anagram (rambling) of TO CHARLIE . Rhetorical = in the style of a grand public speech (rather than as in “a rhetorical question” which doesn’t expect an answer).