I could actually see Ms. Moorehead in the role of Elizabeth, Patti, all dolled up to look elegant and regal (just as she was in the episode of Bewitched when she first came to visit Samantha and Darren to meet her son-in-law for the first time, wearing a fashionable outfit and ringing the doorbell rather than popping in). It would take some imaginative creativity to consider her in the part, but stretching it could be done. But you're right. I could clearly see her as Dr. Hoffman. I think in that role, she would've remained more "crusty" with Barnabas, even after they became friends, rather than as a love-smitten woman as portrayed by Ms. Hall. There would've be no misguided romantic interest, but I'm sure if Ms. Moorehead did it, she wouldn't hold back on critiquing Barnabas' many failed love interests.
"Barnabas, you're almost 200 years old. It's time to grow up and stop looking for someone to take to the prom."
"Oh, yes, Julia, as if your dance card is filled."
"I don't need some romantic relationship to be 'filled.' And it's not like I'm immortal. Your clock stopped ticking and still you can't find the right woman in the want-ads."
Gerard