I have the feeling that people think that GHC is less rounded that it is due to the myriad of extensions one needs to enable to bring some functionality in (MultiParamTypeClasses + FlexibleInstances + FlexibleContexts come to mind for any class-based programming). This is one of the reasons I wanted to push the new GHC2020 "standard".
I agree. A frequent comment at events is that Haskell is just too complicated. But I think what the speakers often mean is that there are too many extensions. I've asked what people mean, and I never have felt I've gotten a more satisfactory answre than that. Happily, it's a relatively easy problem to fix!
That said, I do think writing out some goals would be a useful exercise.
Richard