How did the first Darrin really feel about Aunt Clara.

Even though he was sometimes annoyed by her droppings-in and her bungled spells, Darrin really had a soft spot for her. Dick York was the only Darrin to interact with Aunt Clara because Marion Lorne died in 1968, and Dick Sargent became Darrin #2 in 1969.

I agree. I believe Darrin had a soft spot for Aunt Clara in spite of her ineptness.

I agree. I believe Darrin had a soft spot for Aunt Clara in spite of her ineptness.
She was never mean to him unlike some of Sam's other relatives, and every mistake she made was with the best of intentions. Aunt Clara only wanted her niece and husband to be happy. :D

She was the only "in-law" he could stand!

She was the only "in-law" he could stand!
Exactly!! :nod:

The relationship between Darrin and Aunt Clara was established in the touching episode, Samantha Meets the Folks.

She was one of the people that Darrin liked in Sam's family.