Dealing with some degree of aggro mobs outside the leve is reasonable. However, some areas, such as the one the OP cited, and particularly Nanawa Mines need adjustment. More often than not, on certain leves in NM, you'll end up fighting more non leve mobs than leve, which is ridiculous, especially in view of the time bonus. I agree this is mostly a solo issue, but I believe SE stated that leves are now intended for the more casual/solo players, so there's work to be done on some of these.