Smoothening the linings would indeed help. Therefore, I'd suggest a finer-pointed marker if you just can find one; that'd make things much easier.
As for the minifig, even though the green sharpie could be more smooth and solid (there are some white spots that could be covered, and some parts of the colour are darker than others) it doesn't really look that bad. The visor, on the other hand.. The colouring is pretty decent - the shade of blue is nice - but the design could be greatly improved.
Basically, the problem with the visor is the widht; it should be a lot narrower, like in this
picture. Now it looks.. somewhat swollen, actually.