The play Betrayal by Harold Pinter is not an example of either psychoanalytic or feminist drama. In terms of genre, Pinter is sometimes loosely associated with a school known as the "Angry Young Men," writers of lower or lower middle class origin who were disillusioned by the elitism of British literature and politics after World War II. Although Pinter is similar to Osborne in being actively engaged in political critique and rebelling against the gentility of Georgian literature, his own work is technically more modernist, tending to a sort of dark absurdism, sometimes called "comedy of menace." His hallmark as a playwright is use of awkward, almost menacing, moments of silence within his dialogue.
There are two basic approaches one could take to staging Betrayal. First, this play is quasi-autobiographical, reflecting his own experiences of adultery. Thus it could be staged realistically, using 1970s settings and costumes, with the very mundanity of its setting contrasting with the awkwardness and menacing silences of the dialogue. Such a production would work well in a theater with a proscenium stage and substantial budget for set, costuming, and props, as this sort of detailed authenticity can be expensive.
Another common way to produce Betrayal is a very stark, minimalist production, with an abstract setting, perhaps just white or black blocks broken up with odd cracks or gaps, in place of realistic furnishings and stark spotlights on the characters. This sort of production works best in innovative spaces rather than traditional proscenium stages, and places a much greater burden on the actors to create the complete audience experience. This form of production can be quite elegant, and very much suited to the spare style of the dialogue and the way the words are surrounded by gaps of silence. It also has the virtue of being easy to create on a low budget.