Agility IMO is fun. Once you get the hang of the click intensive side of it, it becomes fun. Especially when you start making smalls goals with it. Record your laps and try run as fast as you can and score the fastest lap kinda thing?
I understand most see it as a crap skill overall, but it's supposed to be a challenging skill.
My least favourite is Construction. I don't know why, I even hate the skill icon. :L