Aftermath: Well, we all know that Outrage and Earthquake are two things that this CAP is gonna hate, and both happen to be physical. Now, this doesn't help it with Latias, or Specsmence, but it's certainly a handy thing to have, especially since if you have SR up, salamence can say goodbye to 50% of it's health before it thinks about outraging this puppy.
Compoundeyes: STAB Thunder that's actually usable you say? YES PLEASE! Sleep powder maybe? How many times has will-o-wisp let you down? No miss Draco Meteor? Pretty appealing (and deadly) I'd say. Be it support or offense, everyone likes reliability.
Effect Spore: If your team is in dire need of pure para support, this isn't the greatest ability around, but still helpful in that case. However, a major draw to this ability is the chance to put the opponent to sleep, sleep is a deadly status to succumb to, allowing your opponent to set up, switch in a counter with little or no drawbacks or just destroy your prized pokemon. The drawback to this ability however is the chance to poison the opponents pokemon, there are 2 kinds of poison, deadly poison (6%*2(per turn)) and poison (12% per turn) with leftovers, poison is doing a measly 6% per turn to the opponent (12% without leftovers, or with leftovers + sandstorm, and 18% without leftovers + sandstorm), not only is it far less damaging then Deadly Poison, but it also removes the chance to paralyze, burn, or sleep the opponent.
Hustle: 180 BP Outrage, being nearly unresisted, is an absolutely deadly force, 98 BP Thunder Fang, 113 BP Thunder Punch, 180 BP Volt Tackle, these are all very powerful attacks, though they come with the cost of their reliability. (Though CAP8, with a decent amount of SPATK, could run thunderbolt/draco meteor, just in case it can't risk the miss, or needs to hit a physical wall)
Mold Breaker: Jolteon eats thunderbolt, levitators eat earthquake/earth power (whatever the hell we decide to give it), heatran can say hello to neutral fire, it's definitely a useful ability, though not the most useful.
Rock Head: Volt Tackle, Brave Bird, Wood Hammer, Flare Blitz and Head Smash, some of the most powerful moves in the games, with some of the biggest drawbacks, rock head of course eliminates those drawbacks, and allows these powerhouse moves to be used to their fullest.
Static: I've been using ampharos in UU (occasionally OU =/) to great success, but the job could definitely be done better by CAP8, I really love seeing ambipom u-turn off ampharos only to return to the field paralyzed by static.
Thick Fat: 4x fire resistance and a 4x electric resistance, as well as neutral ice damage, thick fat is definitely a fine choice for an ability (though Draco Meteor and Outrage are WAY scarier then anything Mamoswine or Glaceon could throw at CAP 8)
Trace: I love Trace... I love it so much... flygon might still be able to rip open CAP 8 with outrage, but salamence and gyarados get intimidated, heatrans fire blast is absorbed, porygon-z (if adaptibility) will eat a 280 BP Draco Meteor (and NOTHING wants to switch in on that), tracing wonderguard would be absolutely lovely :3
Unburden: Who doesn't love a +1 speed boost, especially when it could allow this thing to get the jump on salamence, latias, flygon, and other deadly dragon types.