Top 5 in no particular order:
1. Monk of the Four Winds (Elemental Fist is a vital versatility option for monks to have flavor beyond stunning fist)
2. Crossblooded Sorcerer (Gives everyone more customization both in abilities and backstory/heritage.)
3. Swarm Master Druid (Anything that gives Druids more unique options out of the gate makes them that much more interesting. It also allows for smaller creatures to be more viable if people don't want hulking beasts following them around all the time.)
4. Winged Marauder Alchemist (Animal companions for other classes is always good, and this allows alchemists to fill a ranged niche easier. Make it for all races and give us some better bird options for both medium and small characters)
5. Incarnate Paladin (Was never in Pathfinder specifically, but you guys made it in the August 2003 issue of Dragon Magazine pg 53. It was a true neutral paladin of the balance of nature/elements and it was really cool flavor.)