Can't help you with the staggereds. I don't do them very often.
But on color... ...what you're seeing with the mixing colors is a product of different portions reaching different temperatures and differing surface conditions across the coil, the latter of which affects both heating and oxidation. A dirty coil with shorts will have mottled colors, interior legs that are different colors than the ones next to them, and so on.
You want them glowing evenly the first time, so the idea is to pulse out the shorts at very low wattage. Don't let them glow when you're tweaking the shorts out - you need to have all of them out before the first glow-pulse. Do it for longer than you think you need to. Make that first glow a good one. This part is trial and error. The idea is to be as brief as possible. A longer pulse will give you a deeper color, but at some point, the color is going to gradient out from the center, which is a nice effect, but apparently not what you're going for. You want to get *just* into the range where it starts to turn. Kanthal will give you blue/cobalt before yellow, green, and purple. Nichrome gives you gold, then purple, green, and blue.
With some skill, you can even control the colors you get. You just have to get the wattage right. If, for example, the coil jumps right up to the point where it turns green and then starts rapidly cooling, it won't have the colors that come before it reaches that point because it wasn't at lower temperatures for long enough that they bloomed out. It's easier to shoot for the first colors initially. Once you can do that, you can start shooting for the secondary colors.
You just have to get it on the first pulse. Just one quick, high-powered pulse. Sometimes you can "fix" things with a second or third, but that usually introduces more colors and/or washes them all out. Once you get a feel for it, it's not too hard to hit the sweet spots, but it takes practice. You have to observe the turning points for different coils at different wattages. Lower-mass coils will turn easier.
Which reminds me, the mass of your outer plays a role, to. Thinner outers will generally turn more easily. Makes it easier to hit the later colors because they cool faster, whereas a fatter outer may continue to turn after you let off. And since it cools more gradually, the outer wraps will be a different color.
One thing that helps is to watch how it glows. If it travels from the center out, the color will reflect that. If it glows evenly, the color will also reflect that. It's important to get enough power that the whole coil lights up immediately. You can "prime" it with a few mid-power pulses so it'll hit that point more readily. Once you successfully hit the threshold for a full-coil glow the first time, the duration determines what color you get.
Another consideration is cleanliness. Any oils on your hands can cause non-linear variations in color - i.e., color splotches. Make sure you clean your hands with a fairly strong soap. None of that moisturizing BS. Also worth considering is your wire. Many times, the wire coming off of the spool isn't totally clean. Clean enough to vape off of, sure, but not totally clean. The best way to completely deal with both finger gunk and dirty wire is to toss your finished coils into an ultrasonic cleaner. That will get everything off of them. As long as you have clean hands and ensure minimum handling when mounting (only touch the sides/legs, use clean tools as much as possible, and so on,) you should get a nice, uniform blush.
Nichrome, imo and ime, doesn't directly affect flavor. What it does affect is heat distribution, which can change the flavor a little. Whether or not it is noticeable depends on the coil. Nichrome definitely blushes more readily and vibrantly though. Something to consider when trying to take color shots.
