The outer lobulated OIII rich nebulosity has come out very well indeed.
Very deep. The inner H-alpha rich nebulosity is burned out. Should be easy to fix.
Many professional scopes produce very pretty haloes around the stars. I Presumably internal reflections. You are in the best company. They are not necessarily from the filters. Could be the CCD window for example. That it shows up most strongly in OIII could be because you have to stretch the OIII the most to get a good image, or it could be to do with surface coatings.
Good work.