I've used that middle tie-out and some shock cord to pull straight up for additional tautness...gotta have something conveniently right above you for it work though....
I like your tarp! cause i have the same one~
Why did you decided to add the webbing? I used the grommet instead. I added a prusik knot to the ridgeline and through the grommet and used a toggle to secure the ridgeline.
Also, if you don't want to sew and reconfigure your tarp (the bottom spacing grommet), you could use a small rock and secure the tarp https://youtu.be/nP_AsTcK3mw 1:17
I was going to buy me a War Superfly but I guess i could use my tarp for this season. My Dream Hammock should be coming in two weeks. i can't wait.
Good luck with your hammock camping~
Randy from NJ