I agree especially with your last point. But I think that this is also tricky, because UE4 went F2P basically, that changed the whole game. Professionals as well as casual developers are all mixed in the same bowl. Trying to accommodate both is definitely going to be a challenge and in many cases, content creators will most likely opt to target one of the 2 audience. Who is likely to make them more money, the professional or the casual dev? I guess this is highly dependant on the number of purchases which is bound to significantly change as time goes. In light of all this, has anyone tried the donation route? How well does that work in the gaming industry? This is an option that I am strongly inclined towards in order to have initial prices lowered. But perhaps I have too much faith in people 
I would like to note that I do not agree with the original op’s #1 post (And anyway, the content creators can alter their prices at any time). The whole “I just want part of the system and not all of it”, like said, message the content creator and chances are he’ll find a way to release a simplified version of his system if it can pass through the submission process.
Regardless, this topic warrants some discussion.