If you are full time explorer you won't miss any xian items, as for the legendery items, hold on to your xian skull, he will eventually tell you where to look for the clues for all legendery items and when he says so, you should go and check that place cuz that's when npc will be there or I was just lucky enough Or just follow the old A3 guide. Also talk with all inn-keeprs and buy their drinks.