Fantastic choice for your "last" snake. I really think you'll enjoy a short tail. I am a million percent happy with my Borneo. They are definitely slow moving and easy to get good pictures of!! Juice will literally just sit in my lap and chill, barely exploring. He'll look around a bit, get comfy and put his head down and stay put for a while. Then move around a bit, get comfy and chill. Definitely no worries about him going too far!!!
So far, another short tail (either a blood or a blackhead sumatran) is the only snake I'm consider adding a second of.
Anyway, awesome choice, he's gorgeous!!