The bloody Terminator look on 360° was as bad as the mullet, super uncool, not to mention the rhinoceros pants and jacket and the fugly shades.
People also seem to forget that the Fly hairdo was very hit and miss, some nights it looked good and even great, but on many nights it was just odd and misshapen, unkempt, not to mention he sweats so much during gigs it was slicked back for most of the concerts' duration. Plus on bad days he had a dyed black Bill Maher look, and that isn't great.
The Joshua Tree/R&H era mane looked quite good, but I wish he didn't try to go back to it on Vertigo, that was really bad too.
The Elevation hairstyle was just an inferior, boring take on the Fly look, the Vertigo semi long cut was also a variation on that, with much less hair available and aged skin, making him look worn out and untidy.
I clearly prefer the close crop, buzzcut look, he has a good head shape for it, good nose for it too. Popmart, NLOTH promo period were good.
Also like the Boy era haircut with the fringe, wasn't cool, but suited him.
Actually Bono's haircuts are becoming a historic epic of uncoolness.