I think you have to include Lillian Gish in any conversation about great silent actresses. Her performance in Broken Blossoms is brilliant.

Probably, but I have not seen much of her work. Did she do comedies as well as dramas?

She did mostly dramas. Her sister Dorothy was the funny one.

Pickford and Swanson were the most versatile.

Perhaps, but your review says they were the only "true actresses" of the silent era. That's a pretty sweeping statement considering how many female stars from the era you have never even seen in a movie. You didn't simply say they were the most versatile. And Gish was most definitely a true actress.