In my opinion, riding on this public support wave the things that he MUST do are the following:
1) Please hire some decent public speaker and work on your public speaking skills. It includes all: the tempo, the gesture, the body language, the texture, style and the content of the speech. Most importantly when to apply what. A Jalsa Taqreer and address to the nation have two completely different occasions and need different style. Even though I support you, but I must be honest, it is a pain in the butt to hear your speech (sorry captain) LOL.
2) Learn a bit of diplomacy. You can be diplomatic about refusing someone something and will still get the same end results. There is no need for black and white categorical statements
3) Do not focus too much on accountability for now. Our institutions, especially judiciary are corrupt to the core. There is no need in wasting so much energies there. Focus on more important matters of the republic and show progress. Appoint right people in the right departments and things will automatically start moving ahead. Do not talk too much about it in public.
What else do you think he should do to get more seats this time and after that being a more successful in governing?