OK this may be a little similar to the emotional heart of Indy thread but anyway...
All of the Indy films after Raiders have been deviations from the basic Raiders Template that is why the Indy series has avoided James Bond deja vu or the law of bigger bangs in the Die Hard series or improving on the same story endlessly in series like Terminator:
Raiders was a pure pulp action-adventure film with a flawed hero and exotic locales.
ToD sought to make itself very different from Raiders by apparently throwing away the formula, and dragging Raiders pulp action and villainy to its logical extreme.
So ToD set itself apart from Raiders by giving it a different location (although still very pulpish) and making everything far more black and white as well as being more action packed than Raiders.
After the relative failure of ToD LC marked a return to the Raiders format, but the Indy of LC is very different this flawed man/hypocritical man we met in Raiders is turned into a crusader basicly in the purest meaning of that word.
Also the film is made far more character driven with the relationship of Indy and Henry dominating.
Also as much as i hate to say it Last Crusade is a buddy fick in someways with Indy having a large supporting cast, and him coming to a respect for his partner (Henry)
So we have had a pure pulp adventure which in my opinion does not need to be re made in sequel terms or bettered, something different and action focused and Indy as a crusader in a buddy flick.
What will be the new spin on the series this time, i am not really talking about new characters or an important actual plotline just how Indy IV will be different (in a good way) from the trilogy.....