Setting filter options is a good way to deal with it. Another option is setting hot keys for cycling through mobs in the enmity list. When I play on my laptop I have all my controls set up so I don't need to use a mouse and I rely heavily on the hot keys I set that cycle through the mobs only in the enmity list. It does take some getting used to, especially if everything in the list has the same mob name, but once you are accustomed to it it's much more intuitive.