I build boats for a living. We use a lot of control cables most of the paddle shifters I’ve seen use a Morse marine style cable. There are different grades Standard and Teflon. The Teflon is better but the most important thing is the geometry of the linkage. The system needs to be set up to use the full travel of the cable which is normally around 3″. If you don’t do that then your putting a higher load on the cable and your exaggerating the effect of the play in the cable. The right cable in good condition with the right geometry will shift fine.