"During the key-creation process, you'll be asked to enter a passphrase. I often leave this blank to avoid having to enter the passphrase each time I try to connect to another system"
I would respectfully suggest that it would be better to use a passphrase, but to also use an ssh agent (Pageant, ssh-agent etc) which allows you to unlock the key once, and then use the agent for authentication from there on. You get the best of both then; protection for your key, but also protection from shoulder surfers and seamless passage from machine to machine.
If that's your view, why are you even on this site ??!