Intimidate is ability numero uno.
So much of 5th Gen physical offense is patently absurd. Excadrill and Landlos deal obscene amounts of physical damage, and those are just the tip of an iceberg that includes Garchomp, Salamence, Terrakion, and Gyarados. Intimidate blunts this offense and gives CAP 1 that many more switchins. The fact its typing makes it neutral to Rock, Immune to Ground, and resistant to Fighting makes it ideal.
This one will seem odd, but I'm suggesting Sand Force.
Sandstorm is just as ubiquitous this generation, and Sand Force provides us with two crucial elements: The first is immunity to Sandstorm damage, which allows Leftovers sets to keep their considerable bulk. The second is that Sand Force can boost some coverage moves that have specific use against a few common threats. Evem if the only Ground or Rock attack CAP 1 gets is Hidden Power, the boost brings Hidden Power Rock to a respectable 91 Base, perfectly suitable for addressing some of the more dangerous Flying-type threats like Thundurus and Gyarados. Since none of the moves boosted by Sand Force are STAB and only Rock gains significant coverage, it gives CAP1 more flexibility in Sandstorm. Combined potentially with Hurricane that will give it a power boost in Rain, CAP1 will be balanced enough to take advantage of the two most common weathers.
[17:53] <&Deck_Knight> If I Cite and Prune CiteandPrune's post, what does that make me?
[17:54] <Birkal> a citeandprune cite and prunner
[17:54] <%DHR> O_o lol
[17:54] <+Mos_Quitoxe> Cite and Prune doesn't do enough of either
[17:55] <+Mos_Quitoxe> can we make him change it or force him to pay damages
[17:55] <&Deck_Knight> It would be a lot easier for him to Cite and Prune if we made him a mod.
[17:56] <&Deck_Knight> I delegate this task to Birkal.
[17:57] <Birkal> >:|