As the title says, The desert region of the map needs finishing to open the map fully. After that, the minor details can be dealt with.
I have to get Cactus Sap (Structures plus mod - Propellant - Cactus Sap, Sulphur and oil). We can get 2 of the ingredients with a little messing around but not Cactus Sap without the desert region unlocked. Alternatively a few cactuses for the time being on the sandy area near the Green Obelisk.
After that, snapping of platforms on the redwoods so we can get Sap for Sweetcakes without doing a song and dance routine to get it.
However, opening the entire map so we can use it all should be a priority. Even if only the basic landscaping is done for now. I have noticed there are dino spawns there already, it needs only landscape clean up and the berry plants etc put in.