Gravatar is really simple. There isn’t much there other than your list of email addressess and the image you want to use with it.
I thought it was rather odd/mysterious too some big “in thing” that would absorbe time. It’s not. Very simple and easy to use. It’s like a utility.
One account tied to one email and a password. You just then go in and add emails and upload images, or select from their library.
No cost, no ads (when you aren’t there–don’t remember seeing them) It’s just set it and forget it.