Well, after 9 days of contemplation, let me say this:
- That's a hella funny story about the eight legged cat. Kinda funny how much processing and interpretation of the world we take for granted.
- For my own part, I'm not thinking too much about the freedom from the 'rules'. I'm sure I'm following many rules without thinking, just by having seen so much art. Frankly, the two of us are at different places in the journey and I'm still trying to understand how to draw hands and clouds, so I don't have time to worry about conformity just yet. For me the block is more often like "I want to draw a pearlescent tiger riding a cupcake-shaped motorcycle - but I don't know how" and then settling for a yellow cat sitting on a tricycle. I'll leave it to you to break free from the shackles of the medium. 
- I guess maybe you went to art school or something, but it seems to me that most pixel artists definitely did not, and so pixel artists are much more free to draw laser-dragon-robots. It's gotten to the point where it's refreshing to see some pixel art that is actually related to the real world, like politics, music, personal experiences or day to day life, as opposed to games, pop culture and crazy fantasy worlds. Or at least a combination of the two, like a platformer game where your moustached Ukranian plumber is attacked by Russian turtles and piranha plants. 
Yes, I will agree this time :) I generalised and forgot that people, even before any personality develops, differ very much in how much they are self-criticizing and self-doubting - not entirely related to actual skill they have and level of awereness of it. So a kid can be proud of a crappy drawing not only becasue they don't know how crappy it is, but also becasue they are "enlightened" and confident (in a healthy or unhealthy way).
I also agree about that bravery, but I'm not sure I would call it that. And I understand the academic artistic education is all about "draw what you see not what you know" which kids are still free of, but I wouldn't say that kids draw differently becasue they draw what they "know" (read imagine), not what they see. It is always a mixture but kids are not yet tought what is culturally expected (which is kinda good I think). My perfect example i remember is a kid who drawed an eight legged cat. It happened not becasue had a such amazing imagination (which we adults often envy), but becasue looking at a cat from a side they sew 4 legs, and from the other side also 4 legs, and was asked to draw it a in top view :D
I do miss the freedom I had before knowing anything but this is a standard thing in any arts forms. Same with music. People who learned any music theory often feel limited in composing, compared to what interesting things they could come up with before having any theoretical knowledge. This freedom (is supposed to) come back when you internalize a healthy relation to "rules" that they are a language of description of what is already good, not a set of limitations for creating something good. Or the freedom will get back when you reach the master level. :D
I would also like to find out what, where and when culturally limits drawing laser-dragon-robots as apropriate for children only... and kill it.
I would first say that it depends on age. Expectations and self censorship definitely increase with age, and also with forming a clear identity around skills. Children will often notice that things are wrong or difficult, they may ask adults to draw something for them, but it certainly depends on age and personality. I can certainly relate to your experiences, but I also remember an age when I was not like that, and I certainly remember my friends not having that angst as young children. They would happily show me drawings that sucked. Secondly, children do have different personalities, some are more critical than others. Thirdly, as a teacher I have observed how different children and teenagers approach art, and it's striking how brave they often are. I tend to limit my attempts based on what I know, but children are often free to draw robot dragons shooting lava showers without first deciding that they lack the required anatomical knowledge. But of course, children are different. And a lot happens between the age of 4 and 12. I'm just trying to channel more of the courage and fun I had at certain times, when I would pat myself on the back for a crappy pirate ship or dinosaur.
I wish to strongly dissagree in a very friendly way.
There is a very well remembered experience from my childhood when I was fantasising or anticipating my drawing result, to be utterly dissapoited with it, which looked nothing like I was imagining it. It was frustrating and many times made me cry. I had no advanced terminology to explain it and had no idea myself nor adults to explain to me that this could/will be better after years of practice. Adults just tell you that your drawings are beautiful and that's it. But it was definately a worrying about lack of skill to draw something.
My wife has an artistic education and had exactly the same experience. I can confirm also observing that among some peers back then and looking at kids now when I'm an adult myself. I do not have enough data to find any corelations but I do have an intuition that this is happenig only to so called "talented" kids who are expected by adults to draw better than other kids (and then they internalise the expectations in a bad way). Or kids who have acces to art (thanks to older people) and are aware that drawing/painting can be serious and how well the results could look.
@Wayuki: Thanks! There are 3 big and deliberate inconsistencies in regards to light. I'll call it artistic license. In regards to the little family, it's partially justified in that the person on the left is blocking much of the blue light from the window, directly from the left. The person on the right is blocking much of the orange light from the fire, directly from the right. On top of that, it depends on the colour of the robes. If the robe is blue, it won't reflect much orange light and vice versa.
Also, there's a bit of pretentious symbolism going on here with fire and water, which made me want to bend the laws of physics a little. Overall, I'm happy with that.
@Flinigan: Oh thanks! I went out of my way to make this one a bit cleaner, with outlines, contrast and all, so I appreciate that!
@gawrone: Definitely ambitious for my skill level, but I'm trying to maintain a childish attitude to art. Kids never worry about whether they have the skills to draw anything. Then adults go taking themselves too seriously and get all angsty about pixel art dragons. At least I do.
@pixl_person: Thanks, I cheated and used a tutorial for that one. 
Really cool scene! The lighting directions on the 3 midground characters is inconsistent though, with the hooded figure being lit from the left and the other two from the right. If there are two light sources in the scene, all three figures would catch the light from both directions.
Just wow! Such an ambitious endeavor finalised with such amazing result.
Thanks, man, appreciate it :)