I think it will be just fine as-is. If I were to tweak it for my palate I'd ditch the 60-minute addition, move the 20-minute addition to FWH and move the 5-minute addition to flameout. But the way you have it is perfectly fine. My way may end up closer to an APA in hop aroma, but that's just my tastes.
I agree with Mort on the wheat. Any beer that has a halfway decent amount of hops is going to get more head retention from that than wheat malt. It certainly won't hurt, but I think you can safely omit it.
What kind of earthiness are you looking for in hops? Something like Fuggles or Willamette will give you that "forest floor" kind of earthiness. If you have access to Caliente you can get that same kind of earthy note along with some fresh peach/plum type stone fruit notes. Either way, I prefer to have my earthy hops as a flavor addition and my fruity hops as aroma when I'm mixing them. I'd do Willamette as FWH and Amarillo at flameout if I went that route.