Nothing wrong with learning new aiming methods, but there is really no connection between an aiming method and a bow, except what you make of it.
I like my arrow length to be the same between field tips and broadheads, because arrow length does affect point of impact (POI) if you use the tip of the arrow to aim. That said, there will be some small difference between the broadheads and field points because of the different length of each, even if they are the same weight and are mounted on the same length shafts, but it shouldn’t be enough to throw you out of the kill zone if your form is otherwise good.
If you want to learn split vision, which is what I use, range is estimated subjectively, rather than in yards or meters. The better your range estimation ability is, the more accurately you will be able to shoot, but range is estimated by thinking, “the arrow point looks right THERE” rather than, “I think the range is 27 yards, so I need to have a gap of 24”.” The most important thing is to always focus on the spot you want to hit with the arrow point in your out of focus peripheral vision. If you let your focus drift to the arrow point, it’s best to let the shot down and start again.
Differences in shooting downhill or uphill are minimized if you keep your shoulders and torso aligned in the magic T, by bending and tilting at the waist, rather than lowering or raising your bow arm. That said, there are still differences, and you need to practice uphill and downhill shots until you figure out what adjustments (if any) you personally need to make.