IMO the thick fog retracts from the valheim experience of exploration. I just killed the queen after exploring about 10 mistlands in order to have a more informed opinion.
After many playthroughs I am always excited for a new swamp/mountain/plains. Even though they are hazardous and difficult to traverse there is something cool in the exploration of looking around in the distance to find hints of useful resources and progress. The mistlands is another story. I hate that type of eploration. Maybe the first 1-2 times it's ok to build the feeling of danger and i get it. After exploring multiple mistlands it's enough.
Proposed solution. Give as an upgrade to the wisp light that greatly amplifies it's original range. Make it use materials from mistlands so that we have to experience the first time hard exploration but prevent it from being tiresome after a while. Black cores maybe? They seem to be irrelevant after you get the first 15 for the crafting stations.
Valheim is one of the best games of all time in terms of replayability. Invest in that.
Source: https://www.reddit.com/r/valheim/comments/zxak0t/the_wisp_light_is_too_weak/