This feature is sorely needed. Right now, playing melee is just a chore. Targeting enemies like the little spitters or the snakes is just a pain, and you are more fighting the UI than the actual mobs.
As for the "skill" required, this doesnt remove any interesting skill.
To do well in the game, you'll still have to have proper positioning, build, reaction time,and so on. But when comes the time to finish the lesser mobs, you'll have a good time doing it.
I mean, this is just good UI really. The previous very successful games in the genre had this feature for a reason.