There is no better all-around "go to" ball at this time than the AI. However, that being said, any medium to medium low RG ball with a solid PK18 cover (Nemesis) would have to be a close second. I prefer the AI over the OI or ZC - as it covers more territory, and can be made to fit almost anywhere with surface tweaks. For those rare times when it starts up a bit too soon, I go down to a Danger Zone (Nemesis would work as well).
You can't go wrong with either the AI or Nemesis. Let budget be your guide.