I really think kids are a lot smarter racers than Most adults give them credit for. And they are specially smarter than those adults who are getting into the sport late. (Example: C riders---true C riders.) Every 85/65 race I watch/announce I rarely see kids making poor decisions when it comes to jumping for a pass or any combination getting around slower/lapped riders.
I see more carnage in the Novice adult classes than I see in Mini classes. That almost seems backwards, you'd think it be the other way around!
That being said, I wouldnt vote for a beginner mini classes. Jr Mini is beginner enough....that's where most started. And yes, there can be a huge separation of speed but kids advance faster as riders than any adults can. (And you can nay say me and hiss and fuss over that last sentence all you want. My opinion on that is about as rock solid as my neck brace opinions, can't convince me otherwise.) But again, I'm never in the majority of thinking when it comes to MX. Whatever the class structure ends up, so be it. At this point there's no reason for me to cry about it unless I start my own Organization, which I will not and cannot.