The gains are subtle and take some experience to fully appreciate.
In my opinion, they are quality components. They are serving me well. Of course, you can buy eyepieces and barlows that would cost a lot more. But the gains you as a beginner would see are in no relation to the difference in cost. The gains are subtle and take some experience to fully appreciate. I would strongly advise you to not "upgrade" anything on the scope itself at this time.