Going back to the OP's ask to make the worms more impactful perhaps leverage one of the horrifying mechanical pieces of 5e. Exhaustion. If you get worms you get a level of Exhaustion. Even if Lesser Restoration removes the worm disease it cannot remove the level of Exhaustion. Worse exhaustion builds up over time if you get worms multiple times over the course of the day it could get scary very quickly with no quick fix. Even Greater restoration only downgrades exhaustion by 1 level. This would make the game tougher for certain Barbarian's paths so you might need to warm players of this. Some 5e tables dislike the exhaustion rules so only use if you think they will enjoy. At higher levels giving them means to rest magically might be an option if you find it too much.
I ran a 3.5 Age of Worms campaign. It was quite tough for the players even once they could deal with the worms, especially once they reached the Spire of Long Shadows. Retelling of certain campaign events still occur at the table over 10 years past. Hope it gives your table great memories as well. Enjoy.
I ran a 3.5 Age of Worms campaign. It was quite tough for the players even once they could deal with the worms, especially once they reached the Spire of Long Shadows. Retelling of certain campaign events still occur at the table over 10 years past. Hope it gives your table great memories as well. Enjoy.