I would agree that generally, you shouldn't worry about it too much. However, if you are worried about copyright infringement, there are a few small technical measures that can make it more difficult for casual rippers to get away with it. The first measure is to use PNG files, and embed a comment with your copyright in it. This is fairly easy to do with, eg, the Gimp. , Secondly, you can hide some kind of visible or invisible mark in your image (watermark). For example, you could use an indexed (palette-based) image, and then hide a text or logo by using a color that has a different index but looks the same. Finally, there are some steganography programs out there that allow you to hide all sorts of data in an image invisibly. You should decide yourself whether the last two suggested techniques are really worth the effort.

Of course, none of these measures is foolproof, and they can all be circumvented by someone knowledgeable enough. But I think some of these techniques might be helpful, especially embedding a comment, which I think is  generally useful, because it clarifies the copyright of your art to people who have no intention of ripping your art. Also, someone may find your sprite on the internet without a way to contact you, and  mastilla y want to contact you (say, to hire you). In that case an embedded comment with your e-mail address in it will be very useful.

Just a suggestion for the shoulders.

Oh, and not to sound harsh, but I think you should try to decide yourself what look you are going for. It's difficult for me to see which version is closest to what you want it to be. I think it would be easier if you told us which is your favorite edit.

Finally, I decided against shaving of one or two pixels in the width, because, no matter how I tried, it just looked to scrawny and weak to my eyes, not to mention it didn't fit with the head. I was from the beginning dead set against presenting my women like barbie dolls, so I feel like i'd rather have my character look too portly than too skinny. Remember, it's not fat, but muscles! ^_^ I also decided against the flipper arms, as they aren't the style I'm looking for. Also, the face looks exactly how I want it to be, so I'm afraid I'll have to reject the heavier brows, which look more manly to me.

However, I lengthened the torso to give a more vertical, slightly thinner feel. I think this works better than shaving off pixels. I also straightened out the shoulders. I updated the outline to use two colors more effectively. I also borrowed st0vens hand  and texturing/shading technique, so I feel it looks a lot better, now. I also tried to make the ankles look more narrow, but I refuse to make either the arms or legs 3 pixels wide because it just look too thin to me.

Anyway, I'd like to thank ndchistie and st0vens for your contributions, although I didn't heed most of them. I'm thinking I have a more clear idea now about the style I'm going for. 

And Roy Krenkel? Now there's a woman:
http://4.bp.blogspot.com/_zD76GyK9Tjo/Sfu6ydyVLvI/AAAAAAAAAtE/BKtNFCOv11g/s1600-h/tv-rgk1.jpg
^_^

Interesting point of view, Atnas. I guess we can say it's true that creativity can grow from limiting ourself.

Some people may think that pixel art is a limiting type of art, since we can only work at the pixel level, with very few colors. But I was calculating a little, and it can be shown mathematically that the possibilities of pixel art are sheer infinite. For reference, let's keep in mind a very big number, 4*10**79 (4 times 10 to the power 79), or 40000000000000000000000000000000000000000000000000000000000000000000000000000000. That number is the current estimate for the amount of hydrogen atoms in the whole universe!
Now, let's take a look at very small pixel art piece of 16 x 16. How many possibilities are there? Well, it depends on the number of colors. If we use 2 colors, then there are 2**(16*16), or 115792089237316195423570985008687907853269984665640564039457584007913129639936, possibilities, which is "only" 1/345th of the amount of hydrogen atoms, but still, a lot more than there are stars in the universe!

Once we use 4 colors, then there are 4**(16*16) or
13407807929942597099574024998205846127479365820592393377723561443721764030073546976801874298166903427690031858186486050853753882811946569946433649006084096
different possibilities! That's just astronomical! More than there are hydrogen atoms in the universe!

And, if you'd use 24 bits full color, then there would be (2**24)**(16*16) or
3375152182143856118491117448868264047748245269061354378998711510846650037846741324165030982375991521461354629508635213511720607262070
2805213786429827261190495295209725036214861444552245271001884442331336463841183659029156587178439044751051570054376203776342097110897
6401193279180123374243133559193596396525678717812867692707110267091573529243487775155745125792074301249607450177138114756335603617462
4023137218698763328189000397512451741043623275178605325803090424898978434337358002042906439972398162921003968619981201705996204089414
5649613141899373457990136110124033082268445299759214270557020697837444729628470445553597383435232465858124331879290922696980222735667
3323935612163123006229898288296485668393765657478972738362500087728995623901601898523186831764997784754495348973021510834485352883671
3359219844441024401290307061953847602312108701182160272713034206236029269419691503075347557104718762157767773401597106128626624077600
0199761459471444940463293093653202098729357658867135004032110599475307618336429187822239334863636668860337516076025023807524328879162
1421498051541281795034053907109943737835019482117307228603598377500903352726158479078471240691411993347222620555343776990543813708613
3733747157454846874399266047577502857228026799413570499383535597769544263543294619356182101708973662737907113148393068453262295239889
7715491344942216169944540811346628089421863683937920456996873353908785220590722518585909106605811532117238941679346587984132366957891
3577817597952200345811734734797262357003215294955397764406926445582844693488706710559959872030627305252763960269629167183586298455205
5649515251359787092798278577467492976507248514968246279440892612726761606062392337083935905843484661050153215422112962406633569826605
0975882792155955005954460099419877138745992453542401993667168494168245722096801075794308992327588609520244453197182140416
different possibilities! That's a number so insanely huge it's unimaginable!

This interestingly enough shows why it's important to limit your palette when making pixel art. Using a limited palette limits the possibilities somewhat, but with an unlimited palette, the amount of possibilities is bewildering. It also proves that pixel art is indeed, an art, for it takes great creativity to make anything that looks nice within the vast amount of possibilities. Pixel art as the spiritual descendant of pointillism. What do you think about it? ^_^

PS: These numbers were calculated using the Ruby programming language , which has great facilities for handling astronomicallly large numbers.