One trick is to have two worlds. Build on one world, and kill bosses to get access to advanced materials on the other world. That way you'll never have difficult raids on your pristine build world where you've left the bosses alone.

In addition to the console commands, if you just want to progress and gather in easy mode, go to Nexus mods and get Valheim+. It will allow you to tweak a lot of different things like gather rates, portal restrictions, and damage given and received. Turn resources way up and turn enemy damage way down.