You will be happy to know that the trade has increased even more since your figures in the graph:
Trade between India and Pakistan surges 21% to $2.4 billion - The Express Tribune
If we can directly trade what we are routing through UAE (more than 4 billion, probably around 5 - 6 billion today)....we can get around 8 billion+ in trade between the two countries without much effort and increase it from there.
Pakistan however is very closed to Indian manufactured goods....yet there is still a 4:1 trade balance in favour of India...so I would assume more direct trade will produce a figure of say 2 billion exports from Pakistan to India and 8 billion in other direction in the next few years (if direct trade is allowed to happen).
The paradigm of connection is key in this context. I believe that with Japan and China's drive in both India and Pakistan, respectively, in developing critical infrastructure in the two nations -- we can see further enhancement of trade , region wide.