I completed this same object recently (
https://astrob.in/5olbsv/0/) but in narrowband. Looking at your image in broadband, I agree it is not bad, color is good with tight, round stars. I think what is "off" to me is simply the detail is missing, especially given the 30 hrs of data. However, you did not state your Bortle scale in which this image was taken, which could account for part of the lack of depth in the details. Besides that, I think you might be able to stretch the channels further to pull more details out of the data. It just looks to me that it is there, but you need to reveal it further. Since you are using PI, you might want to try GHS, assuming you did not use this stretching tool, and see if that helps reveal more information.