IK did a great job, but things aren't solved in one visit.
That said, his execution throughout the trip was superb. By opening with the massive rally, he was able to project an image of strength in what was supposed to be a hostile environment. He had significant discussions with various business owners to push for investment in Pakistan, an absolute must. He used Trump's reputation as a loose cannon and his savior complex to get him to put India on the back foot. Now every time there's an issue with Kashmir, Khan can say, "well, President Trump offered to mediate peace talks, but you weren't interested." The visits to Congress and the US Institute of Peace really introduced him to the US community.
The one negative I would cite is that the conversation remains too much on security issues. The Fox News interview was an example of this. I get that security is a major part of the relationship between Pakistan and the US, but going forward IK needs to find a way to make economics part of the public cnversation. We know that there are some business issues that are started to work themselves out (PIA direct fights, business investment), but if there's one thing that would really help Pakistan it's working to push capital investment like dams and similar. There need to be more seminars on the "Pakistan Bano" bonds and similar so people have an opportunity to invest.