Agree with others ... the style of the star (gorgeous BTW) and the border (pretty in it's own right) clash .. oil and vinegar!!
I personally like it the way it is ... narrow yellow border and wide black border - it frames the star beautifully.
If however it needs to be larger .... perhaps narrow the outer black border by half, add another yellow narrow border, then add a wide black border to the finished size that you need. So ... narrow yellow, narrow black, narrow yellow, wide black. The end effect will be a double yellow "frame" in black.