The 3rd was considered the strongest Hokage of the four. The 1st had a unique bloodline and the second was a Suiton master, but the third, if I recall correctly, was considered a master of all ninjutsu (Whether he could use jutsu of natures other than Katon or Douton is unknown). The 4th has tremendous potential as well as the "intangibles" of a Hokage. The self sacrifice, the abilities. Honestly, if we look at Naruto now, if you just changed his temperment, he is going down an eerily similar road as the fourth. I mean he did create a jutsu that the fourth couldn't finish in what, a matter of days? At age 15? His learning curve may be the fastest in the mangas.