Thanks, I wasn't 100% happy with the episodes20in20 set but am still glad I made it in time :) special thanks for listing those favorites even from my icon dump, I'm always surprised when people care to look at so many icons!

Sorry for replying so late, I didn't know how to reply to the coloring tips part, I'm terrible at giving advice cause I feel like the best way to learn is just to experiment around... I like that your example isn't an exact replica of my icons, it has your spin on it which i always appreciate! anyway, I'll try to give some tips and links for inspiration:

I think the key to that 'flat face style' is contrast more than coloring. If you want this effect, you want to do anything that darkens the shadows and brightens the midtones but not the highlights, so that the midtones and highlights blend into each other while the shadows are clearly separate. This can be done in many ways and I try to vary it up too so that I don't always go about it the same way. Usually I play with different gradient maps on different layer modes but the constant is that usually the gradient maps I use have brighter colors in the middle and darker ones at the start and at the end. I'm pretty sure I learned the use of the basic copper gradient that comes with PS from one of my old favorite makers called fuuurs; you might want to check out some of her tutorials, she posted them at bourbonate.

Other non-gradient map techniques that can also achieve this effect include:

1) brightening eeeverything quite a lot and then using selective coloring in the 'blacks' section and making the blacks really dark; <--- a lot of people use this technique, I think, but a special nod to absolutelybatty at reflexive_verb whose amazing tutorials encouraged me to play more with selective coloring

2) using a color range selection where you select midtones and then make any adjustment layer at all where you brighten things up; <-- I learned this trick from raiindust who is too awesome for words and posts at aintafairytale, there a LOTS of great tutorials there but I can't seem to find the one I'm looking for rn. Maybe it was just a psd. But anyway, totally recommend checking out her comm because there are lots of fantastic things there. :)

3) making a normal coloring and then using a color range selection where you select the shadows and make any layer that darkens these shadows. for example, in 93 I just made a black color fill layer and set it on soft light and that gave me the cartoonish effect I was going for.

4) the film grain filter can also push the icon a bit closer to this style, cause with the right settings it can brighten the midtones quite nicely while also making things more vibrant. This I learned from the brilliant theotherayn who posts many fantastic icons and tutorials at bittergraced.

these are just some ideas though, you could use almost any adjustment layers to achieve contrast like that. The coloring part is basically what you already did in that icon: using masked layers to color each part individually.

however, there are some risks with this coloring style - it's not the easiest to use and even when it works it's not to everyone's taste cause the result can look very unnatural :p I mean usually I read that you should try to keep things HQ and preserve details in the cap whereas the entire idea of this style is to erase detail to a degree where live action subjects start looking like 2d/illustrations. And the contrast part of it is a very destructive technique, meaning that it super easily makes things very sharp and LQ looking, which is why I need to do all sorts of manual fixing afterwards to salvage some of the image quality. Don't get me wrong, I obviously like the style a lot, but I'd imagine that a lot of people don't! but with this disclaimer in mind feel free to experiment with it, I hope some of these tips will be helpful but I'm not the best at explaining stuff...