India
Now I give the word over to Trin Tragula, who was the main man behind the changes in India.
As it stands now, India in EU4 has 77 provinces. These had mostly been drawn to facilitate the many border changes that took place between 1444 and 1820. They were a convenience more than anything else.
After the overhaul in Art of War, India is made up of 153 provinces. This has added a considerable level of detail to the subcontinent and, much like in Europe, you'll now see a higher province density in richer areas especially. The Indian tax and manpower base has also been boosted a bit to compensate for the added amount of provinces.
As you can imagine, this means both that there is a whole lot more to do for the tags in the area themselves and there can be more historical competition for the ports of the region. It also means the region is more differentiated. You can more clearly tell which areas are rich and which are poor. Along the way some changes have been made to the general setup as well as some new additions in the form of tags, cultures, etc.
Easiest way to see the changes is probably a tour of the new map region by region. So here's a short overview of the area and what's going on in 1444: