Weirdly, I acquired my general fearfulness (which includes a mild fear of heights) at mid-childhood. So you have verylittle!me going off and climbing stuff and generally being adventuresome and imitating Sandokan (a pirate!)--and little!me having changed from reading some books to reading all the time and not stepping into the sun at all. I sometimes wonder at the change, but hey, I suppose it was part of growing up or something. So I would say that 7yo me would totally be all over that, and 9yo me would probably be trying to get other people to do the work while she designs the buildings (what didn't change during childhood: awful tendency to boss around people).

Getting back on topic, how would you design a thing like this to be more inclusive?