Movies from before the 80's appeared not to conform to what is now perceived to be 'Hollywood' timing.
ie - you spend so long developing plot, then action, then plot, then build up then action and so on...
The Godfather seems boring, because its paced slowly. Because its not all tense and action-y and what most cookie cutter movies are today, yeah it seems boring.
I admit, it can be tough getting through it at times, but the story itself and the acting are phenomenal.
I would like to see what a modern director could do with the movie simply using the original footage, but editing it and scoring it in a modern fashion. Just out of interest anyway...
On Godfather... firstly, it has to be noted that its a book first and foremost. And the movie is very good to the look and feel of the Mario Puzo classic.
Secondly, the theme of the movie is not designed to be a shoot 'em up chase 'em down type of action movie. Its a movie with sinister underlines, the growth, development and evolution of motives and politics cynicism to use them. Its more about the characters reactions to situations and how they evolve and become the people they said they never would be.
I hope by editing it with a modern director that you aren't implying it needs to be sped up or more dramatised. This one was great because of the political chess being played - and frankly, having been to Little Italy in New York and the Italian countryside, its unbelievably beautifully rendered to show what these areas are exactly like and it takes it in, and breathes it in, and lives the lives and cultures of these areas. To change anything about the trilogy would be a travesty IMO, and to me, this is a reason it is such a great classic - it's not like Star Wars and the like where new bells and whistles can make it better. It is, quite simply, already the real deal.
McLovin, Godfather and Scarface are the most 'unwoeful' movies available. I'm sure in 20-30 years time you'll have a far worse appreciation for today's mainstream movies. Put in its time and place, they are both outstanding depictions of scandal and anti-culture.