First of all, 'Gone troppo' just flat out sucks,,,,period. Besides McCartney 2, its easily the worst solo effort of any of the Beatles.
Ok, now that I got that off of my shoulders, I like Georges solo output on the whole. I understand Kevins stance though too. One just doesnt slap on a Harrison album and get knocked out. I remember when I bought 'Extra Texture' and thought to myself, 'Man, this album sucks. Way to boring and depressing', but after about 10 listens, I loved it. George takes awhile to sink in unlike Pauls pop and melodies or Lennons meaningful songs whether about depression or love. I like him anyhow.
George would clock in around 3rd for the solo stuff in my world. Ringo's last 5 or 6 albums have been nothing short of awesome in my opinion so he gets the nod for 2nd. John still comes in last.