Ok, first of all, Alakazam doesn't have Magic Bounce. And Jynx with Magic Bounce wouldn't be too much of an improvement, considering it has such poor defensive stats (even worse than Espeon), so a mispredict can lead to an untimely death (or faint, whatever). Magic Guard Jynx, however, would be really cool. It's become immune to Stealth Rock and Sandstorm and would be able to hold a Life Orb without any health loss.
Dry Skin is also a very good ability in the 5th gen. Its main downside is the increased weakness to Fire and the damage in sun, but those get nullified in Rain and the Fire attacks can be walked by other Water types in a Rain Dance team. Plus it gives free healing like Rain Dish and an extra immunity to a commonly used attacking type. If Jynx had a Rain abusing move like Thunder or Surf, that and Dry Skin would've made it a much better Pokemon.
