There are a number of others who spring to mind, who have their comedic interludes in between other more serious material: Eric Bogle, who could take you from tears of laughter to abject misery between 2 songs: John Tams, who invariably has his audiences in stitches at several moments in any performance: then the recently departed Michael Marra, whose observations of life in Dundee could be totally hilarious.
On the other hand there are people like Les Barker, probably best known for his funny poems and songs, but who has written some very hard- hitting really serious stuff too