Several things cause me to wobble at full draw:
First is too high of a holding weight. Just because I can draw the bow back does not mean I can hold it into the back wall. A 60lb draw at 65% let-off has a holding tension of 21 lbs. 80% let-off drops that to 12.4 lbs minimum. My most comfortable hold weight is around 15 lbs.
Second: Wrong draw length: If its too long, you release arm elbow has dropped down to where there is no more movement to get more tension of the string. This means you are holding more draw weight and have no movement to counter-act it. If the draw length is too short, many people have a tendency to bend the bow arm elbow or hunch their bow shoulder. That is a lot more unstable than a straight bow arm with bone-on-bone contact.
Third is unstable platform: If your whole body is moving, you may just need footwear with a stiffer, wider sole. My yard where I practice has a lot of uneven ground. Footwear makes a difference for me in how stable I am.
Your statement that its wobbly at 30 yds implies that its better at 20. If that is the case, than that means when you have to raise the bow higher you start closing control. That sounds more like hunched bow shoulder (which locks the shoulder so you can't lift the bow arm) caused by too short a draw length, or too long a draw length where you can't pull enough tension on the string to keep the bow up. Could also be just too much weight on the bow and the bow arm still needs some strength building.
I have one bow that is 60 lb Max DW and 70% let-off. I have to back it down to about 56lbs to shoot it well even though it is the lightest set-up I have. My other two are Elites that I have set to about an 80% let-off. They are over a pound heavier with the sights, etc, but I shoot them at 62lbs and shoot them better than I can the light one. I just have s-coil vibration dampeners on all three, no stabs, so cannot comment on if stabilizers would help you.
Hope this helps find the problem
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