Yes, I tought about this a lot but wanted to give it after the Champion. I felt the original games offered more authentic team building without it. After the first Pokemon League run there is still things to do and I tought exp.all was fair in that point. But I got your point.
Yes and there is an explanation for that. A guy in Inferno City Dept. Store 2F has something to say about this.
But I noticed there is bad availability for leaf stones before Inferno City. I'm adding some in the next fix version.