Quick tip, don't extend the smallest section of leg unless you have to. It is the weakest and wiggliest. Having it up inside the second wiggliest section of the tripod helps cut wobble tremendously. If you do extend it, try to only do it as little as possible. And, push the center column down as far as you can. Your strongest extension section isn't in play with it set up as you have it. Fortunately, most of the shots can be taken seated, and that keeps your tripod more compact and those skinniest legs coubled up to cut wobble. That tripod isn't the best, but for seated shooting, it should be acceptable.
Fluid heads are great for glassing to grid a mountainside. For shooting, you want a head that locks up tight. A fluid head, if you lock it, you have to lock it in two axis.
And, switching from a saddle to an ARCA is a huge improvement.
When you get an ARCA rail, get a long one. It adds versatility to your position if you are going to be shooting from different compromised positions at strange angles. Sometimes where the tripod sits and where you sit, pushing the gun back makes all the difference. Also, you can run it all the way to the front and go prone with the legs splayed out as flat as they go.