Best you're breaking my heart here

Picnic as good as the play? I think it shows (as do South Pacific and Camelot) how Josh Logan was apparantly a brilliant stage director (Havign directed those first two on Broadway) and then his all too literal opening ups for films nearly ruin that magic. The 10 minutes of random shots of people at the picnic in particular are awful.
Cat on a Hot Tin Roof has those brilliant performances but the scipt is just too gutted for me--I know that's censorships problem and not really the fault of the director (if anything it at least carries the play's feeling over--something Brooks' next Tenn Williams film, Sweet Bird of Youth didn't manage to do with its changes) and I enjoy the film but would never rank it as highly as the play (especially what I've read and seen of the Elia Kazan original production).
(Ditto Bus stop--I love Monroe in it but the play is so completely rewritten it's hard to compare--I will grant and agree with you on Inge's Come Back Little Sheba though which, even with mild censorship works as well as a film)
Three underated Williams' adaptations are Summer and Smoke--never a success on Broadway, I think it works well as a film even if it's never in my top picks--and it's appropriately faithful. One of my fave Williams plays (in my top three) is Orpheus Descending--he blamed it flopping on Broadway on the fact that Elia Kazan wouldn't direct it as he was busy with Dark at the Top of the Stairs, but Lumet's film version, Fugitive Kind, is surprisingly faithful given the extremeness of the play, and very good I think (even if it divides critics--and it was both Kurt Cobain's and Courteney Love's fave film which I'm not sure is praise...) The only thing with Kind is the TV adaptation of Orpheus Descending, with Vanessa Redgrave and directed by Peter Hall based on his 80s revival just blows it away--but it's not technically a film and isn't on DVD yet so...
I also think Gore Vidal's adaptation of Suddenly Last Summer is brilliant--it took someone like Vidal to manage to keep the heart of such a shocking play while still appeasing the censors (something Brooks never could do IMHO for Cat or Bird) and the star power works magnificently (even my poor Monty's drugged up state works...)
E