I agree with the majority of your suggestions, especially for the gim chest, there should be multiple scattered throughout the game. Herb supplies/stock should certainly be more than 1000. Or at least a faster respawn rate for each of the items. As far as Nieve's cave goes, it should be reworked and maybe even customized and filled with minibosses/mobs for more content. Poisoning weapons should definitely be reworked as it is indeed broken (Dragon p++ arrows pog). I can't say that I've done many Tzhaar tasks while playing, but I can see how they could be annoying. Alternatively instead of Tzhaars only, make it "complete x fight caves". +1 for DT rework for them though @Chimpamzee
TL;DR - Yes.