@ßrit; First, I'm not a pro arb, so take what i say with a grain of salt. The veterans of this forum might have better ideas. Disclaimer out of the way, that setup looks safe enough, but it does require you to grab above your hitch, pull and hip-thrust, all while keeping a tight grip on the rope, at which time you have to reach down with one of your hands to tend the slack, correct? If you can figure out a way to add in a life support rated rope with the ability to be adjusted in length, in between your saddle attachment point and your caribiner, you could push your system away from you, which would allow you to place your hands below the hitch. Then when you pull rope, the system would tend itself. A rope bridge saddle with an adjuster added, with a really long rope bridge, can provide this sort of flexibility. You must make sure that you can still reach your hitch, whatever setup you decide on. Another setup I've never tried, that might help in this regard, is called the "O rig". Something for you to research.
If you've never been to the "climbingarborist.com" website, you owe it to yourself to visit there. Dan Holliday, the host of the site, has created a comprehensive set of videos that go from how to tie knots to complex climbing and rigging systems. All free to view.
Here's a link to the main page of Dan's website.
http://www.climbingarborist.com/
Thanks for listening, and welcome to the TreeBuzz forum! I think you are going to like it here.
Tim
P.S. Here's another link to Dan's website, a page that gives a short biography of the gentleman, to give you a feel for his background.
http://www.climbingarborist.com/about.php