I believe its about 35-40 degrees at the steepest part at the red banks.
I'm pretty certain there is going to be a nice boot track all the way up. (assuming avy gulch route?) It ends up being like walking up a steep staircase. At least that's how its been the past couple times i went up that route.
May- June is prime time so there will be a gang load of people going up the same way.