21a: Behaviour unbecoming. 5 letters. A???O
26a: When in Rome,not one of the BoI polloi! 8 letters. ??e?e?a?
27a: Spin around rapidly 4 letters???r
22d: One measurement that we all might appreciate being reduced.5 letters
??r??
23d: Not a lot! Tiny even!4 letters ?i??