I boot my Mac mini from external SSD and have TM backup and a backup on NAS of my system
Initially I used to clone with CCC my SSD on internal HDD but I don't do it anymore, and some applications like 1password get disappointed when they find a copy on internal storage.
I was thinking that I can remove internal OS X partition and use my internal HDD for other staff
Note sure if that could cause some issue like on system update
I also try to do it but disk utility wan't let my format the internal disk I guess that I can do it booting from recovery
Initially I used to clone with CCC my SSD on internal HDD but I don't do it anymore, and some applications like 1password get disappointed when they find a copy on internal storage.
I was thinking that I can remove internal OS X partition and use my internal HDD for other staff
Note sure if that could cause some issue like on system update
I also try to do it but disk utility wan't let my format the internal disk I guess that I can do it booting from recovery