You, sir, are a brave man. Very brave.
Joe had a nice voice, but it was too close to Lou Gramm's for me and it lacked that turbocharger effect Bonnet's voice had. But I've heard that comparison to Brian Johnson before and it's not inapt at all. And I had issues with his look back then too (but grudgingly accepted how strong his voice was), but a couple of years later (with shorter hair myself) I thought he was cool and ahead of his time. And he had the kudos to get a fresh James Dean haircut when Blackmore "forbade" him to get one, wanting him to grow his hair long(er). (Let's not talk about Joe's hair here and how it is always and always has been in great shape. Or Ritchie's!
)
To restore this particular line-up's credibility here (Roger now with an Ovation Magnum II, bass-promiscuous as he always was):
That said, I think Bonnet's best recorded work was - some high points with Alcatrazz apart - with MSG on Assault Attack. Dessert song is such a classic and no one can sing it like him (you hear that a lot from other singers that Bonnet's vocal lines are impossibly hard to replicate). It's also Michael Schenker's best album outside of UFO.
Bonnet came from an utterly non-hard rock, much less heavy metal background, he considered himself to be blue-eyed soul.