I discovered Frankie Miller from a sampler I have called Vital Vinyl, Vol. 2. It features artists who were on Chrysalis like Rory Gallagher, Blondie, and Ian Hunter!
I was blown away when I heard Be Good To Yourself. If I say that I've never heard any voice like this, people will write to me and ask if I've ever listened to Rod Stewart, which I have. Stop comparing people to other people. People imitate what has been done years earlier all the time today and no one says anything about it. They are both singers with raspy voices.
Listen to the music and listen to what the music industry chose not to promote. This is the case with many great artists because why would people want to listen to something different? We're encouraged to listen to the same thing over and over again. Don't let the music industry tell you what to listen to. Choose what you want to listen to.