A bouncy, energetic, slightly mysterious postman.

A big lug. Probably wears work coverall & tool belt, carries toolbox etc.
A sweet middle-aged lady with a midwestern accent (she's from Minnesota). She can be dressed in bathrobe, slippers and curlers. (In the second act she is underdressed as Johnny Angel. Hairpiece with curlers should pull off. Bathrobe should be rigged for tearing open.)
A dashing, debonair, good-natured man. A cross between Ward Cleaver and a matinee idol. Right out of a Sears Catalogue, or an arrow ad come to life. Although very strong and confident, he should not be lecherous or leering: he's very polite to women and in fact very charming.
A nerd. Loud, obnoxious, inappropriate and unappealing. Costume suggestions: glasses with tape, beanie with propeller, highwater/too-high-waisted pants, pocket pen protector, loud jacket etc.

Earnest young man. Tries to be cool but is really just a regular guy. Has been dressed 'dreamy': white jacket, tux pants, pink tie & cummerbund. Also in some productions has been dressed 'cool': leather jacket, tight jeans, t-shirt etc.

Mr. Postman Milt DudmanJohnny AngelWasher RepairmanMrs. Halo