Am I using the targeting system wrong or what?

[Souljacker]

The only time this method does not work well is if you are fighting multiple mobs with the same name.

Any solution that involves "clicking" is not an optimal one. Tab targeting is the chosen method for the experienced tank, a tried-and-true method to cycling your abilities around evenly. Targeting just needs to make sense, and in this game it doesn't. I don't know who thought it was a good idea to target the furthest enemy away first even when you drill down all the filters to ONLY target aggoing enemies...
But that's SE for you.