I would probably agree that Pakistan has had the hardest process. Historically, Pakistan has been along the route being followed by waves of fighting forces travelling from one area to another - not a good location for trying to build a stable government. India is so geographically diverse, it struggles to find agreement between different regions, but it has been more protected from outside influences.

I would say Pakistan.  Pakistan faces serious difficulties in creating a stable and democratic country.  It has suffered from military rule and the power of the military.  It has also suffered from the fact that its tribal areas are very difficult for its government to control in any real way.