Hi! Welcome to the forum
How is the Ultimaker 2+ working for you?
For the Eiffel Tower, it looks pretty small in size based on your photo.
It also has a lot of details and small strands in it, so you probably want to go with a smaller nozzle than 0.6.
travel speed is the speed your printhead travel at when it is not extruding. Do you know at what speed it was extruding?
When you say thickness, what do you mean? The walls or top and bottom thickness?
Overall for such a detailed print I would suggest to go with a small nozzle, print fairly slow and at a low temperature. Good luck!