Like Midnight said, it would be helpful to post more information about your Pokemon so we know what you're trying to do with each one (there are multiple ways to use Tyranitar, for example).
What I can say right off the bat, though, is that you should only use 1 mega Pokemon on a team. Some Pokemon function perfectly well without their mega form (Tyranitar, for example). That being said, Mawile and Kangaskhan aren't fantastic choices for playing in OU. You can keep 2 out of 3 of your potential mega Pokemon if you don't use a mega stone on Tyranitar. This means you just need to replace either Mawile or Kangaskhan. I would suggest replacing one of them with either Hydreigon or Togekiss since they both have great synergy with Aegislash. Since Aegislash and Hydreigon/Togekiss will cover each others' weaknesses, they make a pretty sweet core.
Yo, isn't Finneon an Eevee evolution? I mean, it has -eon in the name...