Well, aside from the fact that she's at least a decade too old for the role and that it's highly doubtful she could or would sing eight shows a week ever again (the last time she did, it destroyed her voice), she has the completely wrong sensibility for Mame Dennis. While she can be funny in the right role, she's too sweet, too regal and a bit too schoolmarmish for a part that requires a certain madcap energy and effortless insouciance. She's also never really demonstrated a particularly well-honed facility for tossing off one-liners, which is vital to the role. There also is a bit of a "tough broad" underneath the all the elegance in the two definitive portrayers -- Roz Russell and Angela Lansbury -- that wouldn't come easy to Andrews (if, in fact, she could summon it all).
It would great to see Andrews do a musical project again. What about Desiree Armfeldt in "A Little Night Music"? Sondheim wrote the role for an actress who can sort of sing (Glynis Johns was the original), rather than a singer who acts, intentionally restricting all of her music to roughly an octave or so (which is, I believe about what Andrews says she has left - her middle range is fine, but she says the high notes are all gone). She certainly could act the role well.
Other than that, she's probably better off doing something on film or television, where she'd have the freedom of multiple takes and access to all of the technical enhancements a music studio can provide to cover up the present deficiences in her singing. Wasn't there a rumor that she and Carol Burnett were thinking about doing another one of those "Julie & Carol" concerts? Hopefully, we'll see her again very soon.
"What a story........ everything but the bloodhounds snappin' at her rear end." -- Birdie
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"The Devil Be Hittin' Me" -- Whitney