We have a female yorkie and a female mini-aussie and they are best buddies. They play very well together and we've never had any issues with either one of them. My daughter has a large dog about 70 lbs. and my yorkie gets along great with him too. Only problem there is when Dakota hits Gracie with his tail and she almost falls over.
A lot of this has to do with the dogs personality and how well they are socialized but I would be inclined to chose a breed similar in size and temperment.