One massive main near spawn, 7 permanent bases close to the 5 bosses and one each at the north pole and south pole. Before I started wold hopping near the end of the game, each of these bases had smelting stations for the various ores in those biomes and the plains base has a farm. Beyond that, I keep 4 temporary outposts (north/south/east/west) for further exploration and resource exploitation. Permanent bases are a bit more elaborate while the temp bases are rudimentary shacks with portals and wooden fences. When I push on, I just take the portal materials from the temp base with me to the new site...I have "abandoned" bases everywhere.