If anything the bike is rich at idle, so I don't know what would be gained by going to larger pilots, given that it's less than 1 turn out now.
There's also no hesitation, & the midrange is strong, so what would a shim accomplish?
Perhaps the point is that not all bikes respond the same way.
It's atypical go smaller on the pilots, but that's what the situation appears to suggest.
Perhaps I should lean the screws more, give it a try, & assuming that everything else is good read the plugs at idle & if that is OK then be happy. But 158's & 40's are daring me to give them a try...