Like QuiltE says, you've already identified many of your issues. I'm big on ergonomic stuff and cannot stress enough the importance of a quality adjustable chair with the right seat depth for your body. If you are on carpet, a mat makes a huge difference. You need to be able to adjust your chair if not your table and our needs change greatly from day to day, week to week, and even hourly. It is not set once and forget.
When choosing a chair at the very least you want up/down height. You should have an adjustable back support. Arms are up to you, I find I like having them but they often get in way of the table and then I'm not sitting correctly. The seat depth needs to work for you -- watch out for chairs that create a pressure point mid thigh. Be aware that cheap chairs are for smaller people (150lb and under) -- if you are a larger person you need a chair rated for your size. It was super hard/expensive to get hubby a gaming chair when he was big.
For friends with lower leg issues, some find benefit by using start/stop buttons and not foot pedals. Some have ramps or those bicycle type exercise things under the table.
Vary tasks. I used to have my quilting room set up very efficiently, I could sit in one spot and twirl from cutting table to sewing to ironing without getting up. I also became very sedentary, seriously under 500 steps a day during covid. I kept my sewing machine in the sewing room, moved the cutting stuff to the dining room table, and the ironing board to the living room. helped to have a supportive husband. Almost immediately I was over 2k steps! Plus I turn on energetic music and do what I call the "stompy dance" at the ironing board.
I prefer to do every piece at a time while quilting, that can mean hours... now I look at 15 minutes a time at a task. 15 minutes of cutting leads to 15 minutes of sewing which leads to 15 minutes of ironing (all more or less) and then I do another round.
Fooling around with not quite right stuff is not worthwhile to our bodies. Change those rotary blades often! Get handles for your tools that work for you, I recently bought an expensive custom made wooden seam ripper because I can't handle a lot of the cheap ones any more.