I'm always a little puzzled when people say that Dolly (the character) is a cartoon. I don't experience her as that--not when the production, direction, or actress work to ground her in emotional reality. There are certainly farcical elements to the musical, as well as to Wilder's play, but I think Dolly's monologues to Ephraim give her depth and nuance--we see and hear the loneliness that is also there in the crafty businesswoman (who may also be a little desperate--why else would she pass herself off as able to do everything under the sun?). I'm trying to make her into something out of Strindberg (but wouldn't Carol Channing have been a fascinating Miss Julie!), but she's not cartoonish to me--nor are Horace or Cornelius or Irene.
I don't think, by the way, that this contradicts what does seem to me to make sense--there's enough room in the role as written for each actress to bring her own personal stamp to it. So, I'm not surprised that Midler's Dolly has a touch or more of the Divine Miss M. in her--who should she be channeling, Miyoshi Umeki?