Here is my current cable routing, and I am not sure if I will change it up.
Initially, I had run it down the seat tube, thru the linkage and then up the cable stops for the front der. I didn't like where/how the cable slacked and ended up sticking out from the frame. I also didn't want to get it pinched in the linkage somehow, but it all looked clear.
Now, with this routing (shorter hose), I just run it through the RS Reverb guide tied to the seat tube and it has a long unsecured loop that goes up to the top cable guide, then to the remote (mounted upside-down on the left side, one of the benefits of the 1x9 setup - VERY clean and ergonomically friendly).
With this routing, you can see where the cable accumulates when the seatpost is slammed. When it is extended, it more closely follows the top contour of the shock. It doesn't bow out towards my legs and I don't see it being a real problem of snagging trees or anything. I'll be watching the cable for any signs of wear that have to do with it touching the linkage on the outside, as I anticipate it might be in contact too much over the course of time.
I really don't want cable slack accumulating out back of the seat tube where the wheel will catch it - I've seen that happen with several different setups and looks like a quick way to end up with a hose worn out/ripped out mid-ride.