But make sure you make at least a 2 copies of your backup. Many people have lost their coins due to corrupted USB or hard disk or due to accidents like fire. Printing the private key in paper and storing in a different location could be a good backup or self crypting the private key and storing it into cloud is another great idea.
I don't like the idea of storing the keys in the cloud, even if they are encrypted, there is a risk of someone will hack your account, access your keys and find the way to decrypt them. About the idea of printing the key, I think it could be better to write it by hand on a paper instead of using the printer.
the problem with printers is when they are shared printers over a network and also when in certain cases the printer has its own memory that is storing the things it prints and keeps it there. it can simply be avoided if you empty that memory or if you do the right thing and print the encrypted key to not only protect it against cases where printer saves it but also protect it against the case when someone sees the paper you just printed.