I think the only arguments to be made are Bonds, Aaron and Mantle. If he’d been healthier, Mantle was on a hell of a trajectory. But he wasn’t, so he didn’t quite make it to the pinnacle.
I think Aaron gets a poor reputation as “just” a power hitter, but he was an incredibly complete player as well. He was dominant for decades - how many players do that? Well, Mays did that, and there aren’t too many baseball historians that place Aaron ahead of Mays. Their offensive numbers are really similar - so the tiebreaker has to be Mays’ defensive dominance. And it really was dominance at a critically important position.
Which brings us to Bonds. BlankSlate made a good argument in the other thread:
Bonds’ numbers are silly. I’m not interested in going back and forth regarding the PEDs (it’s a tedious argument on both sides, and that’s not what this thread is about). If Bonds had been able to play in an earlier era, I think he’d have hit 900 home runs, because he simply wouldn’t have been intentionally walked 688 times. Bonds’ Giants weren’t a bunch of shitty players either - it wasn’t like he was being walked so the pitchers could face Mark Grudzielanek.
Bonds was also a good defender - he won a bunch of Gold Gloves in LF. He was a demon on the basepaths as well. But if we get to consider how Bonds could have done in a different environment, we get to do the same for Mays. What could someone who hit 660 HRs when the mound was 14 feet tall do in the expansion era of the 90s?
Their WAR numbers are really remarkably similar. And that’s just as big factor of Mays’ defense and hitting so well in a pitching-friendly era as they are of Bonds’ ability to hit any pitch a million miles. I cast my vote for the guy who’d I’d rather watch on both sides of the ball and go with Mays.