In many of your works, the values are way too dark. I think you could get more exposure for your good art if the thumbnails didn't read like black squares. When you run them through a posturization filter with 4 levels of gradients, it really is just a black square. Let me know if you'd like to know any more, I think I know a few quick tests that you can use to have a better value balance.

I've noticed this, but never changed my manner when working with dark values. I've developed a preference of darkness to overpower light. I know, it's not good to keep this a norm. To be clear, I think you mean the following. I've added screenshots of my projects that resemble your observations. Here here and here. I use the histogram to guide myself when I lay down the light. And as you can see, the histogram says it all. I've taken a break from painting projects and started focusing on other basic stuff. However, I do occasionally work on my personal projects in which I can still apply your insights. If it's not much bother, I'd like to know these quick tests of yours.

Hmm, those examples are still too dark, even though they have more contrast.

So, to check my values, I use a Hue/Saturation adjustment layer, with the saturation set as low as possible so there is no color.

The result is: https://i.imgur.com/F7ABTMu.png

Then I make another adjustment layer, this time a posterize layer, and have the levels set to 4. I also use 5 and 6 levels for finer tuning.

The result of these two layers is: https://i.imgur.com/W44WeUs.png

A black square, but this can be remedied.

For the next example, I'll be using a curves adjustment layer to bring up the values. Since this example is so extreme, I'll have to move the curve way more than I would in practice.

https://i.imgur.com/sVeCYw2.png

Now, from a distance, the image is much more readable.

Next, turn on the posterize layer:

https://i.imgur.com/9Fs2Fg4.png

Now we're cooking. It's completely readable, even with the posterize layer applied. There is a lot of contrast, even in a thumbnail sized image, and contrast is what creates interest.

I use these adjustment layers as I work a project, and create them very early in the process so I can check my values throughout the duration of the project.

Also, I'm fully aware that you're more technically proficient than me at art, but I just hope this helps. Also I don't even know what a histogram is. Anyway cheers

I applied this technique to a current personal project of mine, and I'm impressed with the results. There is readable information with said project, kinda dark but enough light to see the important stuff. I will be using this technique from now on along with my usual work flow. Kinda rare to receive great information like this on this site. I'll try not to depend totally on it, but I will use it as an aid to get better. Thank you for the valuable input Ironwood!

Glad you found it helpful! Say, I wouldn't mind keeping in touch and running my drafts by you for advice on improvements if you'd find such an arrangement amenable. Usually people here tell me to fuck off or make excuses as to why my criticism may be invalid, so it's a very lovely change of pace when anyone finds a use for it.

in less flowerly language: want to be friends?

I would not mind at all. It is great help when we are told what is missing or seems to be out of place. Of course, we must discipline ourselves; information such as yours is valued to those whom are dedicated. I am. And friends are always welcomed. :D