Rits

Thanks ! Lovely work on your youtube. I went to see a colored drawing in one of you videos and you're doing great. 
So the type of brush is personal taste only ? I sense that most digital artists don't use hairy brushes configs. I see mostly Basic round, custom smeary round, to have a clean round strike with some bleed, without bristles.
I see you always start by coloring the whole thing with a brown for the first color layer, then move on with some lighting with a beige, and then you go for the other palettes in detail. What is your reason for that ? It gives you a lighting suggestion for when you're going to add the colors ?

I use pretty basic brushes, round with some soft edge but not too soft. I'm not sure how others do, i'm sure some pros develop a set of customized for universal purposes, but basic should get you through the beginner ~ mediocre stage. 

Most artists I learned from start with dull and dark color and then work their way to the other end of the contrast. i find it easier that way to capture the feeling as I go. I usually have some idea what the part is going to be like before I start moving my pen, but half way though it always turns out different (since i'm not skilled enough yet), but then on the spot I capture a feeling how it would turn out in 3D (including volume and texture), then I continue to explore whatever is there. So you're right, it sorta give me a lighting suggestion.

this is my work: 

I use Sai instead of Corel

Turn the opacity down to 80~90%, a 10~15% of color blending, that brush would handle most of it.

Along with a 90~95% soft end eraser would do.

lso paint in 200~300% size canvas of what is meant to be seen. 

as a gamer, hardcore competitive gamers don't like luck to be influencing more than 0.01~5% . the more luck there is the less skill-based it is. although we'd be happy to land a critical hit and change the tide of the battle, but if it happens too often we'd only feel like, "if we lose its cuz we didn't have luck, nothing to be learned from; if we win its cuz of luck, nothing to be proud of". 

as for majority gamers, they like slot machine basis and skill doesn't matter. rig the system so they would only win after an amount of repetitive attempts, and make sure no one wins the jackpot right after someone else did. there's a specific mathematical formula for stimulating the players that would drive them nuts and pay the most, but i do not possess that knowledge.

a good presentation can change the players' thoughts from "terribly complicated design" to "uber interesting". but of course its very difficult cuz most players dont have the patience to go through a lot of tutorial / tips.

it sounds very chinese medicine knowledge btw, is that where your heading to? 

I'd not worry about a game without story / lore.

Players can make sense of the environment. just by seeing the graphics and designs would build a story setting in mind, its an automated process, a natural habit.

I wouldn't speak for all. And always an option for you, is to release a game without story first, then if it really sells, release an expansion that implements quests.

Although, a single player world like that makes you lonely, when you dont even have NPC to interact with.

The concern remaining is the fact that there are too many out there. Examples include The Blockheads (iOS) and Terraria.

All you need is just ONE selling point that makes yours different from the rest, and its an experience the majority could not find elsewhere, then you'd hit the jackpot,

What other similar games on mobile have not succeeded to do, is refined control. The android ver of minecraft failed completely. Blockheads tried to improve that, but i haven't tested it nor heard feedbacks. So my personal opinion is if you can design the game control / GUI that is comfortable and efficient on android, you'd win my heart.