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This one (coloured skin) is really nice! I'd argue it's a little too white and bright, but the text and the effects are really good. Good choices on stock sizing and placement, I think any smaller would've made it unbearably bright, but you're getting away with it how you've done it.
The colours are pretty good too, I might've made the skin a tad more saturated, just because it feels a little washed out against that white background.
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I don't know what went up with this one, but you've got serious quality issues, especially all over the bow. Looks like you possibly smudged or put textures over it with low opacity or something, but it is looking really cloudy.
I feel there's not enough going on either, the stock you chose probably isn't the easiest to work with, with this particular style, but there is very little blending and foreground effects. It does feel like a smudged background and then a stock placed on top, but I'm not really sure how you could overcome it using this stock. :S
The lighting is a tad bright, but it works with the stock and the style, so it's alright. Would be good with a bit of text, though it might be a bit distracting given your stock covers so much of the canvas...
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Definitely much better smudging in this one. Also, good atmosphere and depth and colours are alright. Again, quality. It's a bit oversharpened and resulting in pixellation.
Just as some general tips for smudging, smudging is really impressive when you have heaps of details, and really solid, bold smudges. So using a solid brush, and starting with a big brush size and doing the main shapes, then going smaller and smaller and fine tuning and adding more details is the way to go. This allows you to get really strong flow, but also really appealing effects so it should be able to stand as a tag pretty much with just smudging as effects. Also, allows you to get nitty gritty with depth by picking different colour tones, and detailing and stuff.
It is a lot more time consuming, but the result is much higher quality tags, and really vibrant and aesthetically good looking tags.
Keep it up! <3