I’ve come to categorize the ways of using a soft saddle in conjunction with a platform: Sitting, hanging, and leaning
Sitting is straight forward but I would consider sitting to be where your legs at or a little above 90 deg to the tree. 90% of weight in saddle, but you also have weight on knees if you are pushing off the tree to maintain your position. Would recommend a pad or knee pads. You can move around the tree easily enough but requires you to first push off. More comfortable with a high tether, but allows more swinging. Easier to go under tether and bridge.
Hanging is what I consider you’re doing when you push away for the the tree after being in a sitting position. This to me has your legs at about a 40-60 deg from the horizontal plane. This is very comfortable way to hang for me. It’s also easier to push around the tree. 70% weight in the saddle. This means it’s the position I’m most likely to move around in, be exposed in, and feel least comfortable shooting from. If you don’t pay attention when setting up this hanging can put you too far away from the tree that you can’t reach your bow without swinging around or standing up. Medium weight on feet. Reduce feet fatigue if you have a angled platform or can angle your platform down. Tether bridge may be right in the way, may be equal to go under or over the bridge.
Leaning is what I feel the most stable in for shooting because it restricts my movements the most and keeps me up right. This would be like leaning against a wall. I’m probably 60-75 degrees from the horizontal, most of the weight is in my feet, and I’m using the saddle to hold me from leaning back. I can not swing around the whole tree, but I can swing enough to shoot around the whole tree. I think this conceals me better, being close to the tree. I can easily grab my bow I’m this position and I use a tad lower tether and shorter bridge. If hunting a straight tree or the top side of a lean I can easily stand up on the platform without grabbing anything. This does put a lot of weight on your feet so you want comfortable shoes. This position keeps me awake, I don’t get sore, and I have confidence when shooting. Easily to go up and over bridge.
If I’m serious about killing deer I’m going to be upright as possible. Someone told me about this when I first started and I didn’t listen but they were right and they probably know who they are. That’s not to say you can’t kill deer in any of the three ways, I’ve not killed many deer but I have killed from all three positions. This is simply how I break it down and what makes sense to me. You can find comfort in each position but there are a lot of variables in there.