That's almost exactly what I use, but I divide the ridgeline into three parts, joined by a pair of carabiners, to which the hammock lines are attached once the ridgeline is up. So it's
treehugger - main line - carabiner - center ridgeline - carabiner - main line - tree hugger
The two main line sections are 7/64" amsteel with whoopie adjustments. When the line is pulled tight before attaching the hammock, I find that it then sags to about 15° when the hammock is added. At that angle the force on the main line sections is approximately twice the force held by the ridgeline. The hammock ropes are dynaglide with whoopies; they are also dealing with half the force of the main lines. The center ridgeline is also dynaglide.
The other thing I do differently is permanently attach the tarp to the ridgeline with prussiks attached to short bungee loops. The whole assembly is packed in a snakeskin. To set up, I hang the ridgeline, unfurl the tarp, and then clip the hammock to the carabiners.
This sounds like a lot of differences for a setup that's supposed to be the same as the one you proposed, but the central idea is the same. The hammock hangs from the ridgeline and it does simplify things. The hammock is always properly placed under the tarp, and once you've set it up the first time you don't need to adjust the hammock ropes to get the correct sag angle. The ridgeline with tarp goes up first and comes down last, so there's good rain protection.