Ive played through this game a bunch of times solo and whether you die or not your block wont hit 20 even if you use a shield from the very beginning. Your swimming will not advance. All that will advance is your main weapon, sprint, bow and mining. Even if you dont die even once and are the most inefficient player ever most of these skills wont be developed in any meaningful way. I'm not saying the skills system is bad at all, its just that it doesn't generally work in the game. It needs some work.

The skill system is even worse for magic which you obviously haven tried. You need about 30-40+ skill to be viable which is not reasonable given the skeletons cant kill anything in mistlands other than the baby seekers and the shield mechanics. Best way to level blood magic is to stand in front of a ballista or use skeletons in the black forest. These skills also come very late in the game so there's really no time to develop them to 40+ and if you try to kill the queen with 15 elemental skill your in for a very very long fight.