XIETIAN
Its great that the MC has past experience with making things which is not something you typically see in apocalypse novels. Sometimes they learns crafts after the apocalypse but very rarely do they know anything before hand. I look forward to see the MC continue to make his own equipment and weapons. I also hope that he learns other melee weapons and doesn't just exclusively stick to a great sword which depending on how thick it is, its great for slashing and defense but most likely garbage for piercing attacks. A halberd would be a great choice because it has a spear point at its end, a hammer head at one end, and axe at the other end. He doesn't really need the axe head, since a greatsword is amazing at slashing attacks, so he could replace it with something else or make it a double hammer head. Plus, a pole weapon, in my opinion is more suited for dealing with multiple enemies especially when it comes to maneuverability in combat. Whereas a great sword is top tier when it comes to taking down big enemies or fighting one on one, that's without taking into account magic and abilities the sword might have. Regardless, he is going to need to learn to use more melee weapons because the swinging radius of that sword makes it useless in buildings with more narrow hallways, dense forests, narrow streets, and alleys. If he was in a desert, plains, tundra, or on water , he would have no problem but his current environment affects how often he can use the great sword.