Nice fluid feel to them, I'm not sure about the last three, I'm never fond of floating things on pages, the actual drawings are nice, I just feel you could have utilised the space a little more, perhaps.
The first one is amazing. I love the colors and rendering. I agree with epidemic on the last 3, but I'm sure they're just sketches. You should finish them up with a background or something like the 1st. Or do more like the 1st cause I love it.
The process works like this : I picked a theme, the treehouse, and did a few sketches. Nothing too definitive since it would be water based media, hence I did not want to control it too much. I laid my wet sheet of paper on a wooden board and pasted it with kraft paper. Once it was dry, I put water on it and very loosely dropped some walnut ink and watercolor ink on it. Based on the way the ink and water behaved I established a composition for a main trunk, added more water here and there to see how the rest could work, applied a napkin to soak it up sometime, adding more ink some other time. Then I let it dry. After that I painted with some more ink to finish the blocking phase, then I used walnut ink and a nib pen for the lines. I drew based on the texture the ink had created at first and made up the rest.
Eventually I added some gouache for the clouds in the background and probably some color pencil and "voila" !
By the way, the title of the first image is a useful piece of advice : "Never surrender your treehouse"
Magnificent. There's a lot going on and I couldn't tell the order in which you did various things
but, it's very impressive how the randomness of the watercolor was used to create the final
composition. Why did you use the walnut ink? (you can tell watercolors and inks aren't my
field) And one more thing. I've tried a billion times to use nibs. I bought quite a few some years
back. All they do is just scratch the paper, the ink never flows, what gives?
"Don't judge a book by it's cover" Frank Frazetta 1928-2010
I used walnut Ink because I like its color and its versatility : once dry you can somehow erase some of it with water. Regarding the nibs I can't really tell you here, you just have to practice the kind of flow you want by pressing on the paper. Try it on a very smooth paper to begin with maybe ?
And thanks for your kind words !