IMO...march to Islamabad in huge quantities...and shut down the capital...
...all peacefully of course...none of that BS burning tires/buses, using containers to block roads, or looting(as that only harms the country and its ppl). Instead block roads(by gathering of ppl) around government buildings making it impossible for movement of these goons(holding political power). Demand that the government hold elections. Then vote these losers out.
This is the only option left short of violence. Any legal measures will be made useless by sold out judges, MNAs, MPAs, etc.