I kinda wing the quantities. I just mix eggs and flour and sometimes a bit of water until it's the right consistency. I used to follow a strict recipe of measuring out 2 eggs, adding enough water to make 1/2 cup, then adding a teaspoon of salt to the liquid and dissolving, then making a mound of 2 1/4 cups flour, and mixing until incorporated. Nowadays, I add the eggs, and then add flour until it feels right, and then either add more flour or water to adjust.
One of the main reasons I don't follow a recipe is because many of my pastas have added ingredients, like pureed vegetables, and those don't always have the same water content. Sometimes, I dehydrate veggies, puree them, and add the veggie flour to the normal flour.
Key with pasta is to keep it basic and fresh. Puree carrots, onions, celery, like for a soup stock, and add a bit for flavor. Or add in some bullion instead of salt, or make a sourdough starter and do a sourdough pasta (make a sour starter, then add an egg and enough flour until it doesn't stick to the rollers). Or use whey instead of water. Or use a mashed up potato added to the flour for a potato pasta. Or use only egg yolks... so many options.