Alright, more C&C:
Steampowered - Things are looking quite fine for you. The mon's right arm (on our left) looks a bit awkward, and the mon's right arm has too much of a pattern on its upper border, which I would suggest you try to make it more curvy to add an organic feel. The vine is really dark in comparison to the rest of the sprite, but other than that, your pallet choice is exceptional. Also loving the shading work.
Bluemon - The shading is a bit flat on the head and vine, and on the middle petal of its dress I would suggest its shading basically flipped horizontally. The arms are a bit flat, but otherwise the posing is very nice. You should try an outline with varying colours instead of just black. Your pallet choice is very nice, however, I would advise you keep it, because it's not too intense variation and it doesn't blend together.
Wyverii - Incredible pallet choice and posing. Shading is great on front sprite, except for the rear arm; however, the back sprite looks kind of flat and could use another layer of shading (except on the side where the highlight is, that just looks awesome).
DougJustDoug - If you want some help for your attempts to make the dress shading better, ElementalPenguin's sprite would be a great example. Your sprite is looking otherwise awesome, and I love the shading on the upper half of the body, especially the vine's highlight. And I'd also like to point out a fun fact about your shiny, that your choice of purple, green and gold is often a great way to appear wealthy, and I believe your sprite is certainly rich with awesomeness.
MektarTheOverlord - I'll agree with Mos-Quitoxe that your sprite is quite small, but if you do increase the size I would suggest leaving the arms the same; they feel a bit clunky and awkward with the current proportions. The shading is good, but could stand to rise along the back edge of the dress. I personally like the colour choice, that red tint to the upper body's white parts is amazing. I think the vine would be better in the yellow, it's a great shade that isn't too dark. The green vine would also look great if it was darker, but I'd still vote for that yellow one.
Doran Dragon - I'll agree that the yellow and blue is an incredible choice. I would suggest adding another level of shading to the back sprite, so that it looks more round. I love your arm posing and how you made the hands round and jaw-like.
Ice-Cold Claws - Your eyes make him look like
this guy right here, because they're so small and dot-like. If you want to go for another look, I'd make the eyes about 1 pixel wider, but I would like it even if you left the eyes the way they are. I would make the vine's border less flat accross from the 3rd thorn, which can be easily done by giving 1 pixel on each side of the longest line to the next lines on each side. I absolutely love your posing and shiny colour choice, it looks so spectacular, and I also find it great that you make the vine's head just as clear as the main one.