I'm a mugger not a spriter, so I'll leave the sprite for someone else to critique. Firstly I have to say I'm very disappointed in you! *Kicks Lone* How many times do I have to tell you to stop mixing skin tones? Bad one, bad! (You've used FE8 Tana's skin tone for the ear, and Sophia for the rest.)
Also you've used what I call the "Lazy Bastard technique" xD (Just named it now) Merging hair is fine and all, but use a pencil to clean things up once your done, especially if you're adding new hair to a face.
-Original mug, as said above has two skin tones, and has forehead hair issues.
-2nd Mug, Do not color in hair in the same color and hope people won't notice, cause frankly it looks horrible. When I placed Tana's blue hair back on, I was left with ugly purple hair which shouldn't be there, color all this in a random (I think 3rd darkest works best) skin tone.
-3rd mug, now you may recolor the hair.
-4th mug,Pencil in the shading, It doesn't matter if you fail, Attempted shading looks better then no shading at all, and both look better then being a "lazy bastard" and leaving the original hair. In this case you'll need to draw in eyebrows as well, since the old one got destroyed (in the example) Penciling in additions is a basic skill you'll need to understand if you want to get better.
Also, on the right where you merged the hair, you've got Tana's dreadlock like thingies merging into Sophia's straight hair, ugly >_< Hence I just put back Sophia's ear, To be honest I think it looks too big xD Though it's better then having funny hair, and the ear on the original was too high up anyway.
-5th mug, Okay, Sophia's hair is a pain, is there 5 shades in it? >_> Damn hippie, anyway I recolored the hair into blue since Tana was sitting on the side and I wanted to decrease the number of colors. Decreasing color count is essential in hacking, as FE mugs are restricted to 15 colors (plus a background color). Anything which has more won't go into a hack so if that's something you might want to do in future stick to the limit.
-The last mug, is just an ugly recoloring by me, (plus a bit of border elimination on the left handside of the face) why did I choose these horrible colors? To makes sure it still looks okay when recolored, to make sure I didn't miss any pixels, and to make you recolor it instead of just using the colors of the original mugs xD
-Other As for making her look older, there's various paths you could follow, the one I'd do being fiddling around with moving pixels around on the eyes and eyebrow,
Essay complete xD