When you use Proofgrade settings, the power and speed self populate depending on the material selected. As for using draft photo, that is one option and at some point you are just going to have to print part of your project and see how it looks. If you like it, great. If not, maybe try hd photo which is another proofgrade option. Finally, I suggest you read through this entire thread to see how an experienced Glowforge user tests, retests and retests to get to a result they like: Grandparents Photo on PG Maple Hardwood