The image is great. Again palette control issues. You have a lot of beautiful light effects, and it's huge, so obviously the colour count even with very strict colour usage would be high. But you have a lot of stray pixels with slightly changed colour, sprayed all over the image. You would have to find them and replace them. This tool is ultra helpful:
http://yanrishatum.ru/pj/?input=https%3A%2F%2Fpixeljoint.com%2Fpixelart%2F140189.htm
Thank you for all tips and this site, really ultra helpful!!