The problems between India and China have nothing to do with any of what you mention. It's about regional influence and, especially, border disputes actually created by the British, none of which would change if China suddenly became a democracy (in fact public opinion is quite nationalistic of both sides so beware).

In fact it's India that has played the "lemme outlaw your products" card against China recently.

On the other hand, India has very good relations with Russia. Russia supplies half of India's military equipment.

Let's not get into invading others as the US would certainly NOT look good, including or especially compared to China...

So, again, your view seems rather superficial and naive.