The biggest problem I see with design systems implementations is too much variation, which I think stems from the fact designers have not actually thought out w

The biggest problem I see with design systems implementations is too much variation, which I think stems from the fact designers have not actually thought out what the User Experience is going to be and how the design system is suppose to facilitate that, for the whole product line Yes, the whole product line. If you want consistency in a product, it has to start with deciding what UX modalities you want to adopt, and sticking to that. Less is more, usually. Don't add a new component until you have actually exhausted the ability to use the ones you started with, if you decide to pivot UX you need to pivot wholesale etc. Getting people to stay on the rails as it were, is seemingly impossible, but when you can, it works very well. I'm abridging a bit (its a iterative process, start with wireframes over full flesh designs and other things) however this does, in a nutshell, work and has a forcing function of actually focusing on the user and product rather than design in and of itself