If you can afford it get a Doepfer Monster case. I have mine half full and plan to buy another one. They have tons of space for larger modules, case covers and handles and solid power supplies for hungry modules. Plus you can stack and connect them as you grow. When I started, I had a Doepfer A100 Basic system that was half full of Doepfer A100 modules and 6U case that I quickly outgrew. Getting a monster Doepfer case was a great decision for me as I love modular and bought a ton of modules in the past year.