You are asking where to go yet your agenda skips you directly past Stanage Bay to Mackay?? What gives?
You could give it a shot getting into the Murray River near Tully, or working over Mourilyan Harbour and the tributaries. All good grounds and well worth exploring. Places like Hinchinbrook are good but take some nutting out unless you have a local in the boat, very big area inside and outside so local knowlege makes a huge difference. Cape Upstart should be working with Spaniards this time of the yr too, but yet to hear reports yet.