I like ‘out of shell’. It’s going in the note book!
I agree about the use of he/she in clues in general. I know one setter who is actively using ‘she’ when ‘he’ can…
I can't see the word play. I guessed the entry from the definition and the crossers. Also, 14a, "Lukewarm old rocker gets holy inside," has that ridiculous "pi" for holy that I recall we discussed before, malone.
Mathsprof...if it's the 'Amuse...' clue, I thought it was quite nifty. You take the first and last letters from a word meaning 'pedant', so he's come out of his shell.