There are several factors here, such as how your wrist is positioned (because the fingers will follow) and flexibility, etc, but experimenting a little gives you more "light" as you more forward. We can learn just as much from our mistakes as the successes.
For example, over the years I've gradually added more forward pitch to my thumb hole with no negative effects that I can see, and I use much less grip pressure than I used to. I don't have a long span, and I have a shorter thumb, which has allowed these changes. Subtle changes can be the difference between striking out in the 10th and splitting...