Consider OAuth log in
I use a password manager to remember all my passwords so this isn't too big of a deal. However, many Product Pains users mentioned to me that they wanted to log in with GitHub / Facebook so they have to remember which email/password they used for yet another service. People don't like having accounts on random products they might not remember.
Unclear what emails I'll receive
Will I receive a daily email letting me know my SSL is working? Or will I only receive email if there's something wrong? It isn't clear to me after signing up for your product how much email I'll receive. Maybe send me an initial email telling me when I sign up or when I start monitoring something?