Bring materials for two portals. Land your Karve in a forest or meadow biome close to the swamp, not in the swamp. If you park it at the shore of the swamp the leeches and other mobs will swim out and destroy it. Set up a portal at your boat immediately.

Bring enough wood for a bench and stairs, and when you find a crypt set up a portal on top of it. Now you can quickly re supply and bring everything but ore directly back to your base. You are going to be collecting a lot more materials than you can carry, this will save you a lot of slogging back and forth. You can build a fire inside the crypt to dry off and regain your rested buff. Mark all your crypts as you find them, you are going to need lots of iron.