I think your plan is perfect. When I started out building my own recipes I had grand ideas, I added a little of this and some of that and a quarter pound of the other, hmmmm, lets try 2, no 3, how about an entire salad of hops? Tastes OK, how to make it better? I had no idea, way too many variables. Start with a SMASH, then change or add one variable at a time. Sounds like a slow process, but actually a faster road to your signature beer with fewer dumpers. Take lots of notes, don't rely on memory. Learn about water, that was my final variable, and it was a game changer.