The Man has a point here.
It could actually be argued that the Han Solo seen in ANH is similar to the Indy we see in ROTLA (charismatic, not a care in the world), as well as the Han seen in ROTJ is similar to the Indy in LC and to an extent KOTCS (slightly more relaxed, more joking). While the Indy in TOD and ESB share no similarities what so ever.
But back on The Man's point, the Han in ESB is perhaps the most characteristic version of the character. Here Han winds up fully devoting himself to the rebel cause, and in the end sacrifices himself for it and the love of his love. I think the argument in Han's favor as a better character has more to do w/ the fact that SW is more connected in its installments than Indiana Jones, which is episodic.
I don't know if this post makes any real sense, just blabbering off random thoughts as they come to me...