Hi Oboe--it's more complicated than you may realize.
First, for those we've already lost, a couple definitions: "delta angle" refers to the tilt of the boot sole on the ski, determined by the bindings--if the heel and toe platform are the same height, delta angle is zero. Raising the heel is a positive delta angle, and as you tilt the boot bottom forward, of course, you tilt the entire boot, which in turn tilts your lower leg forward. "Ramp angle" refers to the angle of your foot sole inside the boot--heel lifts INSIDE the boot increase ramp angle, but don't tilt the boot cuff or your lower leg forward. "Cuff angle" refers to the angle of the boot cuff relative to the bottom portion of the boot, so it affects the angle between your shin and your foot, at the ankle. Some boots have a forward lean adjustment; others can be adjusted by inserting shims in the back of the boot or the tongue. Obviously, increasing forward cuff angle increases the forward angle of your shin (assuming that there is enough range of motion in your ankle--if not, you may not even be able to get the boot on).
All these things and more influence the boot's "forward lean," which describes the angle that it holds the lower leg relative to the snow. And forward leg lean affects all the angles above, as shown in my illustration (see figures 3 and 4, in particular). The shape of your leg is also a factor in forward lean. A thick, muscular calf, especially if it extends down into the boot, acts like a shim, pushing the shin forward and increasing forward lean. Any boot will be more upright for a skier with skinny lower legs (like mine) than a skier with heavy set, muscular calves.
Furthermore, the optimal angle for the lower leg varies from skier to skier, according to the proportions of the rest of the body. When the knees bend, very long femurs move the body's weight back farther than shorter femurs, and may benefit from more forward lean/delta angle, for example.
Anyway, it is way oversimplified to suggest that "delta angle is good." Often the opposite is true. #4 in the stick figure illustration would benefit from reduced forward lean, which could be accomplished in several ways: adjusting the cuff angle of the boot (more upright), padding/shimming the boot tongue, possibly an INTERNAL heel lift (which can elevate a heavy calf up out of the boot cuff, effectively decreasing forward lean), a negative delta angle, or some combination of these, could help this skier.
Anyway, Oboe, many skiers do benefit from a reduced, or even NEGATIVE delta angle--as you apparently do. I am envious, actually--it's an easier problem to fix than mine, and as I said, it's often a sign of strong muscular legs, especially when combined with a muscular upper body and arms (which tend to move weight forward). Many male World Cup racers now ski with negative delta angles. I know a few instructors who ski with half-inch-thick shims on their boot tongues AND platforms under their toe-pieces to decrease delta angle. So you aren't alone, and you should not be surprised!
Do any of the following describe you, Oboe?--thick, muscular calves, relatively shorter femurs, lighter hips, long and/or heavy, muscular torso and/or arms, proportionally large head? Any or all of these factors would tend to make you a candidate for LESS forward lean, which you could accomplish by reducing the delta angle.
Of course, a softer boot, even with too much forward lean, would still allow you to stand more naturally upright. As I said, the more you can bend the boot, the less critical the boot adjustment is. Of course, the trade off is reduced performance as far as controlling fore-aft pressure, and less support when you need to REGAIN balance. Soft boots forgive both technical and fit problems, at the expense of power and precision.
Finally, there is one other possibility that could explain why you like the reduced delta angle, Oboe. Remember that forward lean issues do not necessarily directly affect fore-aft balance. What they do is affect how other joints and bones must move to compensate--as again figures 3 and 4 illustrate. But the figure 4 stance is not the only way to compensate for too much forward lean. Look at 4 again, and imagine that the skier bends his knees more, moving his hips back. Then, for balance, he would bend forward more at the waist and abdomen, and perhaps reach his arms forward a little more.
The result would be a more natural, but very flexed, low, muscular stance--more like figure 8. Many racers like to be more flexed like this--it's powerful and athletic--but it's also exhausting. You probably wouldn't want to ski all day crouched over like an ape. Decreasing delta angle, or otherwise reducing forward lean, would allow you to stand more upright, more skeletally, more relaxed--like figure 7. And you might well like this change! It could result in your sense of feeling "more perfectly balanced fore and aft," not because you ARE better balanced, but because it takes a lot less muscular effort.
There's always a compromise here. Too upright prevents you from flexing low without falling backward, making it difficult, for example, to absorb large moguls. And it may cause a stance that is TOO tall, relaxed, and "loose" for demanding athletic performance. Increased lean increases your range of flexion and forces you into a more alert, tight, muscular, athletic stance. But it may be TOO muscular, causing fatigue, and it may limit the range you can EXTEND without losing fore-aft balance. Tradeoffs everywhere, and optimal for an instructor who has to be in boots all day every day, may be different than optimal for the racer who needs maximum performance for a couple runs, or a couple hours of training.
So complicated! Somewhere, there is an ideal balance between too stiff and too soft, with just the right amount of forward lean resulting from the perfect combination of all the available adjustments. An instructor with a good eye, an alignment specialist, and/or a lot of experimentation can really help dial this setup in. Suboptimal fore-aft alignment forces MANY skiers to compensate the best they can, keeping them from ever realizing their true capability.
Humans are infinitely variable--there is no "one-size-fits-all" in most things. Certainly not here!