It could be that WP overreached a bit, but I don't think so. The swing was against the Opposition as a whole in the first place.
So what they need to do is a whole lot. But just get down to the basics of managing the estate they were entrusted with with excellence, hitting the ground hard on its outreach and tackling issues as they are. Just that a clearer policy direction and governance doctrine is needed from WP's side.
After all, they were the bulwark of the Opposition and took the swing down but not out. As long as the prime candidates of WP are not out yet, there's no real need of change to their tactics. Just stay hunkered down, work hard. We will yet see the blue skies.
EDIT: And probably work with SDP on a common policy platform. WP can moderate the SDP radical policies like cutting 40% defence budget, SDP can give more bite to the WP policy proposals. Hopefully anyway.