A bit of a slog, this, and not a great deal of fun (though 21a made me laugh!)
Any hints for my last two, please?
15d Clever lot, males promoted before relations (8)
?M?R?*?S (*crosser with the other)
I can think of a word for "Clever lot", but don't see any parsing
24a Announcement of written arrangement, a charge on smokers etc? (3,3)
?*?,T?X
Presumbaly some sort of TAX?