"Is 1/4" enough clearance between toe and shoe for going downhill? I'm thinking not but....
Seeking all wisdom/experience."
I have a similar problem in that I also have longer second toes, on both feet in my case. My right foot is also a half size larger. I am not familiar with the shoes you mention, but I have always ended up sizing to the larger foot and living with a little sloppiness in the smaller foot side; I cannot afford to buy a pair of shoes sized for each foot and discard one of them in each size, and sizing down is simply not workable. 1/4 inch of clearance, IME, is not enough. Your feet will swell in the course of a day's hiking, and you will pay the price, especially on downhill sections. I learned this the hard way long ago.