The flavors that you get don't come from the burning tobacco, the "cherry" as it's sometimes called. It comes from the tobacco surrounding the burning cherry, which is giving up its essences as it simmers.
Too much moisture and the flavors are muted. Think of it as a watery broth where the actual flavor providing ingredient is a smaller percentage of what you're getting. Reducing the water content changes that watery broth into a reduction, one where the flavor providing ingredient is a much higher concentration. But you still need a tiny amount of that water.
Since I smoke Virginias or their variants, like Va/Per, Va/Bur, Va/Per/Bur blends, the moisture level that provides me the most intense flavors is just shy of bone dry. I'm looking for a level of moisture where I feel no moisture or coolness from the water content when I squeeze the tobacco betwixt thumb and fingers. It feels dry to the touch, but is still basically pliant, if a bit crispy at the ends. If the tobacco is crumbly dry, where it's going to turn into powder, it's too dry and some flavor is going to be lost.
Aromatics require a little bit more moisture so that the topping doesn't fade out, but it's a fine line between losing the flavor of the topping and the flavor of the underlying leaf. Aromatics require some experimentation to get right. They're not the easiest genre to enjoy.
English, Balkan, and Oriental blends are easily the most forgiving because their constituent leaves are flavor powerhouses. You can have a middling technique and still enjoy a flavorful smoke.
Packing is important, but in my experience, not as critical as moisture levels. Even if you pack properly, too much or too little moisture will still result in a bland smoke. Packing too tight will affect the draw, prevent the leaf from simmering properly, and will likely contribute to a hot smoke, which also affects flavors. Better too loose than too tight.
Flakes require a different approach than ribbon or shag cut. Some people prefer the fold and stuff approach of smoking flakes. I've rarely found that to be an acceptable approach unless I'm setting up a pipe with a folded and stuffed flake the day or two before I actually smoke the bowl. Then, the tobacco has had some drying out time before I apply fire to it. I reserve some flake to crumble up and spread over the top to act as kindling.
Mostly I break up or cube cut a flake before loading up a bowl. I gravity feed the bits into the bowl with a couple of sideways taps to settle the bits, and then lightly tamp the top, adding some kindling to help spread the flame over the surface of the tobacco. Blreaking up a flake before drying also decreases the time it will take to dry the tobacco, and helps the drying be more uniform.
Different manufacturers tin their blends with different levels of moisture. For example, Gawith flakes are very moist and benefit from several hours at a minimum of drying time before loading up a pipe. You will become more familiar with the differences as you try different blends from different manufacturers.
I'll puff to get a bowl going, then I gently sip the smoke. My goal is to be able to enjoy the bowl while keeping the tobacco just simmering at the edge of going out. That's when I get the most complete and intense flavors. This is when cadence becomes important
Lastly, I always snork when I'm going for all of the flavor nuances. Pushing out the smoke through my nose allows me to pick up more flavors. There are more flavor receptors in your schnoz than in your mouth.
Don't worry about the tobacco going out while you're smoking a bowl. Not all blends are easy to smoke from top to bottom. Some blends need relights. There's no gold star for smoking a bowl from top to bottom without a relight, nor is there a gold star for burning every last strand. It's perfectly fine to toss out the last part of the bowl. You won't damage your pipe from trying to turn it into a blast furnace while going after those last few strands. And smoking too fast and too hot makes for an ashy tasting smoke.
There's a learning curve to finding out what works best for you. Experimenting with moisture levels and with packing will help you find the results that you are seeking.
Patience is essential to mastery. Eventually it all comes together and becomes natural.