I think Rigg was too tough, while the Tracy in the book was supposed to be more vulnerable and even a bit neurotic.
As the story goes they needed an experienced actress to help Lazenby in the love scenes though.
But I don't think the result was very successful, OHMSS lacks any genuine romance and there's no real chemistry between Lazenby and Diana Rigg.
![Image](http://i.imgur.com/cnRfmUX.jpg)
Two others actresses that have been mentioned as better choices were Brigitte Bardot and Julie Christie.
Bardot even starred opposite Sean Connery in Shalako (1968) and might have been an exellent choice had Connery done OHMSS.
![Image](http://i.imgur.com/3Il4lEh.jpg)
![Image](http://i.imgur.com/FwQiSjF.jpg)
My own choice would be Madeline Smith of course.
![Razz :P](./images/smilies/icon_razz.gif)
![Image](http://i.imgur.com/cy3TjSq.jpg)
What do you think?