Agreed. I tell most new area players to not venture past speed 7, and have had many come back and thank me for the advice.
I've been sticking with speed 7 discs for the most part. The Valkyrie and Orc are new additions to my bag because I felt ready for the Valk and I needed a reliable forehand disc and went with the Orc. But, I can agree with you 100% about new players not venturing above speed 7 discs.