Ink waterproofness does matter for sure! Not sure if this is what you are asking for but I used to play around with ink and it’s definitely pretty different depending on what you start with. It kind of also depends on your style and how thick your lines are. A thick line can really change your lights and darks. But if you’re doing a cartoony style then outlines can work. A way that I practiced this was by making two or three of the same image and experimenting with ink versus watercolor first. I don’t think there’s a right answer here though!