Jimmyal6777,
First, sorry for you loss, but glad to hear you're pushing forward with doing things you love.
Sounds like you'd like to start with modifying some of your tools to get a start. Maybe you could list the tools that are top priority for you, and we could focus our ideas on those first. Then we can be more helpful, and you'll get more constructive ideas that are actually useful. Pictures of said tools and work area would also be helpful.
My first idea was a wheelchair that allows you to stand up, as much of our tool use is in a standing position. I've seen some recent ones that are manual up/down, which should keep the cost lower, and could be re-engineered if not readily available.
I can empathize with your situation, as I'm currently building a track chair for a client who's in a wheelchair, and is paralyzed from the armpits down, and has limited arm strength, and his hands are mostly locked in a curled position. Because of this, I've designed in many features to allow him to be as independent as possible, and still control everything himself. You can read more about it here: All Terrain Track Chair (ATTC) - Kustom's by Kent

What kind of wheelchair do you have right now?
If your chair was heavy duty, could add a heavy duty arm on one side to support a work area in front of you. Then you could slide stuff on and off of that work area and onto another work bench. That arm and work area would pivot away from you so you could then get closer to your work.
Redesigning the wheel chair to have the large powered wheels in front, and casters in back would allow you to get closer to work areas, and haul stuff around.
A 4-bar linkage on the seat & back portion of your chair could be used to adjust your height with a linear actuator. That could solve a lot of your current challenges, and not have to redesign your whole work area.

I look forward to hearing back from you, and also see what other ideas members have. Hopefully you can get to working with tools again as quickly as possible!

Kent