[2][3] Other roles performed in Scotland with various companies included Mercedes in Carmen, Kate Pinkerton in Madama Butterfly, Angelina Semos in Luigi Cherubini's The Water Carrier (1950), Madam Wanton in The Pilgrim's Progress, the voice of the oracle and then Evadne in Walton's Troilus and Cressida, Suzuki in Madama Butterfly, Mamma Lucia in Cavalleria Rusticana, the title role in Carmen, Valencienne in Die Lustige Witwe (1959), and Marcellina in Le nozze di Figaro.
[5][6] Other roles included the second Norn in Götterdämmerung, Mercedes in Carmen, a flower maiden in Parsifal, the governess in The Queen of Spades, a singer in Sadler's Wells production of Falla's The Three-Cornered Hat, Aninna in Strauss's Der Rosenkavalier, Giovanna in Verdi's Rigoletto, one of the genii in Mozart's Die Zauberflöte, Marcellina in Mozart's The Marriage of Figaro, the shepherd boy in Puccini's Tosca, Amelfa in Rimsky-Korsakov's The Golden Cockerel, Maddelena in Verdi's Rigoletto, Flora in Verdi's La traviata, a maid in Strauss's Elektra, Suzuki in Puccini's Madama Butterfly, Nicklaus in Offenbach's Les contes d'Hoffmann, Evadne and the Voice of the Oracle in Troilus and Cressida, Grimgerde in Wagner's Die Walküre, and Countess Hurwitz in Lehar's The Land of Smiles.
Reviewing her debut as Rosina, a critic mentioned both Howitt and Gwent Lewis (playing Almaviva) sang the "contour" of florid passages rather than executing them accurately.
[12] In a 1953 Covent Garden production of Carmen conducted by John Pritchard and directed by Anthony Asquith, critic Philip Hope-Wallace found all the leads wanting except for Howitt.
"[16] In the recording issues of the live broadcast of Madama Butterfly from 1957, Ira Siff criticized Howitt for "tending to scoop" although he noted she had "strong scenes" with the Pinkerton (John Lanigan) and the Sharpless (Geraint Evans).