Galil Motion Control products is an excellent choice, very flexible. I will be happy to donate the software front end you need to run them, and for educational purposes include the source code if you like. I just happens that that is exactly what I use in my CNC machines and have been using Galil products in my motion control projects for over 20 years.
With the Galil controller, I would start out with the existing steppers and drives just to get the wheels turning, then add on/upgrade as needed.
Here is a screenshot of my CNC software