Ive heard you can also use the plastic wire stuff used it weed whackers/edge trimmers. I cant remember what thickness, but you should be able to sand the edges to be round with a nail file or sand paper.
Given that you also have wrist problems from drawing, I'm going to make a crazy guess here and say that you press down too hard with your hand. If that is the case, learning how to draw lightly will help with both your wrist problem and your nib problem. If you need help with this, use a traditional paintbrush to practice with. You can't mash a paintbrush around like a pen or pencil, the hairs are delicate and will bend.
I would be very careful with using things like toothpicks and grass trimmer cable to replace your nibs. Tablets can be easy to scratch, and once you have scratches in them you are stuck with the bumpy surface. This is another reason to learn to draw lightly.
The wrist problems aren't caused by drawing. I just had a nasty fall from a bicycle from 2 months ago. I'm even surprised you even took time looking at my journal. If you're worried about how I draw, I really don't use too much force on my tablet, they create overly bold lines, especially when always utilizing pressure-sensitive brushes.
Thanks for the tip! Feedback will always be appreciated!
Ha ha, well I guessed wrong that time! I guess you will have to find another solution. But I would still be careful about using nonstandard nib replacements. My old tablet is very scratched up and it's annoying to use now. I am very paranoid with my new tablet.
The reason behind why I won't use a soft cover is this: -I had two tablets before; they are slippery as hell; I can't draw properly. -I love drawing on paper. -the paper and the nib won't work. It creates terrible screeching sounds and my sweaty hands only makes the paper wet.
And so I decided to use rough surface wacom offered me. It's just like the roughness of the paper. I decided I would buy a 1.65mm grass trimmer for the alternative as suggested by the previous comments. Thanks for replying to my post anyways! Feedback will always be appreciated!