first off don't you effects for your text
it makes it look bad instead put a 1pix black outline on
next thing is brushing
i couldn't get your overall goal for this sig so work on that
the colors could use some sprucing up that blue is such a neutral color that it kinda takes away from the sig
border is barely noticeable so fix that and make it a 1px black or 3px border and thats about all i see
i personally like that render you've got there