The Pickle and Artifact are better suited for park riding. The Turbo Dream is best for your style of Freeriding which is how I ride. I love the Turbo Dream. That board is just sick. Handles the pow and still holds up like a champ on ice and groomers. The harshmellow keeps the board chatter at bay on steeper runs. The TD also has a more mellow rocker than compared to the other two boards. I personally didn't like your fourth choice either. The postermania was too soft for my liking.
Trust me, for freeriding, the Turbo Dream kills those other boards.
FWIW I saw a kid snap the tail off his Artifact 1985 a few weeks ago at Timberline. I ran into him in the lift line on Sunday and he was riding an Indoor Survival.