@MarkWeaver: “I have a big snowboarding background where bigger boards are faster, but smaller boards are more fun in the terrain park. That makes me think a 27.5 might be my sweet spot if a 29er is harder to jump.”
This used to be sort of true regarding wheel size and maneuverability, but not so much anymore. Another myth regarding 29er’s is that they are only for tall riders. At 5’7″ I can personally can dispel that one. Take a look at both EWS and World Cup DH and you’ll see that most riders have moved onto 29er’s.
However, the number one thing is to find a bike that feels comfortable for you and geometry is the biggest factor here. There really aren’t too many duds out there certainly not from any of your aforementioned choices.
Speaking of your choices, for around $3K I’d look at The Stumpjumper EVO 29er or 27.5 or the Jeffsy CF Comp again 29er or 27.5er. For the kind of stuff you want to do look for shorter wheelbases, slack head angles and steeper seat angles. I would also throw in the Transition Smuggler or Scout at your price point.
Lastly, many people dig the Orbeas the Rallon being their flagship enduro rig, however I am not one of them. It was fine, but just did not hold a candle to the bike I already ride.