[3.P] Aid Another Specialist

[Chained Birds]

I'm trying to make a Witch (Pathfinder Class) that excels at Aid Another to get the most out of Coven. I'm looking for every bonus possible from either 3.5 and/or PF, but can only think of the following:

Feat/ Team-Up (http://www.d20pfsrd.com/feats/combat-feats/team-up-combat) - Makes Aid Another actions as a move action with anyone with this feat.
Trait/ Fools for Friends - +1 on Aid Another and +1 to your saves against charm and compulsion effects while within 30ft of Aid Anothered ally. (Second Darkness Campaign)
Racial Feature/ Kenku [Greater Ally] - Aid Another become +3 instead of +2. (MM3 monster PC)

Also, are there any ways for non-witches to gain the benefits of the Coven Hex?

[SamBurke]

There's Halfling Opportunist, which doubles your bonus (PF PrC).

I think there are some feats in PF...

Not sure. Saw someone who was optimizing for it, but didn't play his build past level 1.

[Manateee]

You could always become more characters.
Obtain Familiar, Psicrystal Affinity, Leadership, etc. for more stacking +2s.

EDIT:
The Wolfpack tactical feat from Races of the Wild adds a couple Aid Another based maneuvers. But they seem like they'd be odd choices for a witch.

EDIT EDIT:
The Trailblazer system is basically an alternative ruleset for PF. It makes Aid Another actions much more accessible. Even though it'd be sleazy to plug the ruleset's introduction, it might have some backward-compatible materials for normal PF.

[Chained Birds]

I'm mainly trying to abuse the Coven Hex in that people who share the Coven feat can receive a +1 aid another bonus on the caster's caster lvl.

So far, with Kenku it becomes +3 and an additional +1 from the trait. So all other Coven members gain +4 on their caster levels for the round, and all for 1 standard action from my witch. And she can so far do it at lvl 2.