Hello from another fellow blind person. It sounds like most of the assistive devices have been covered. As a blind person the best advise I can give you is to go slow and learn how to "feel" what you are doing. I have bright lights and magnifiers and needle threaders, but nothing works better than "feeling" what I'm doing. If you need a good website for assistive devices for the visually impaired I use www.MaxiAids.com. They have a ton of different assistive devices for different tasks. Check it out and see what works best for you. Oh, I also have a CCTV which has a movable platform (can't think of the right word for it) where I can set my work and blow it up (magnify it) to HUGE and focus to see what I'm doing on what looks like a computer monitor screen. They are expensive ($4G range) but you can probably get assistance paying for one or find an organization that will donate one to you. It's been my saving grace. And it doesn't limit me. I do points or whatever I want and although not perfect it's darn near close. (And it had better be 'cause I'm a perfectionist, lol)! As for marking dark fabric, I just use regular white school chalk. It's easy to see and it washes right out. It's perfect for marking quilting lines. I also have a hard time seeing blue (most of the quilting pens are washout blue and it's too lite) so I bought childrens crayola washable markers. Just pick the color that works best for you on the fabric you are working with. I always cut off a piece of fabric and mark all over it first with the marker and let it dry. Then wash it out to make sure it will wash out before I mark all over my quilt. I hope this helps. GOOD LUCK!!! Oh, also, I got some VERY POWERFUL magnifying glasses I got from my Dr. You can't buy them at your local pharmacy or WM. They are made in Germany. They are 6X. They also make a huge difference. Also very expensive, but with the right dr. you can get assistance paying for them or with the right organization you can get them donated for free. Sorry this is so long but I wanted to make sure I covered everything. There is so much to cover and I didn't cover it all so if you have any questions, feel free to PM me. And again, Good luck!
Check out my avatar, it's my seeing eye dog. Handsome, isn't he!!!