I would do what is best for you and Trixie. My two both have top knots, but one day I may decide to cut them. Top knots are a bit of work to maintain, but I think they are adorable
I think yorkies without them look like puppies.
One of the things I love about yorkies is their hair. You can cut it so many different ways to give them a different look. I am totally bored by short haired breeds.