Barmaid...depends. of course must be matching. Lace, black and basques, definately a NO.NO.
Material is of the utmost importance...lycra, satin or silk.....although the latter seem to be in short supply. Colour, again depends on type of underwear...burgundy, yellow or white (champagne) and if the latter, has to be lycra.
For a special occasion, after dinner on the rug and in front of a log fire...then French knickers and bra ( these can have a modicum of lace.)
Nightdresses similar, but MUST be knee length at most.