Roads. I play co-op with my wife, we go gather stone and dirt to make path blocks, then we make runs to extend them further and further N-S-E-W.
Explore. We run around in cloth armor but carry a set of iron plate. Look for caves, switch armor, start exploring quickly. Hopefully try to find exposed ore or a translocator, then see where that goes. (make sure to label them on the map... something like 1A for the waypoint of the translocator you find, then 1B for the translocator you emerge at. It can get confusing trying to get more limestone and it took two translocator hops to get to the limestone area if you didn't mark them well). Hell, we have roads going halfway across the map, we have about 8 translocators and still haven't found a desert or jungle biome. It's now a goal to find them just because.
Smithing. It takes a bit to get to the iron age. It takes twice the effort and materials to get to the steel age. Spring through Fall there's a lot of work with the crops, so the winter is a good time to chop down a lot of trees for coal, gather fire clay, quartz, olivine, ilminite (if you can find it) and limestone for refractory bricks, and then generally start the laborious process of making steel tools and armor pieces. If you're already at that point, then winter's the time to just crank out ingots so you can replace the tools during the warmer months more quickly.
Prospecting. While you're extending roads, pause to take ore samples... it comes in handy when you need something if you make descriptive waypoints.
Quarrying and Crafting.. all the time-consuming work to make things look better than the starting cobblestone and dirt blocks.