This is a difficult question.
Age and height are not much difference and besides, the one thing would speak for one of them and the other thing would speak for the other one.
From their looks I would give a little edge to Lita. But I read the autobiography of Lemmy in summer. And he knew both of them and said something about them. Unfortunately I borrowed the book to a friend and so, at the moment, I cannot take a look, what is written exactly. But he wrote, that Lita was too nice for ........... ............. something. It was not catfighting, but it seems, that she had more of a nice personality than a very hard personality. I dont know anymore, if he wrote something about Doro concerning her toughness, but Doro is friends with former box champion Regina Halmich, what might have a meaning or not.
All in all, I would give a very slight edge to Doro, but I am really not sure.