A middle ground would be nice, but it doesn't exist for The BRF. Estelle will never have to deal with the level of harassment that George does. Remember when Madeline moved to London, she quickly ran home screaming realizing it was much worse than she had ever experienced. They treat their own royals even worse.
If William and Catherine dangle George and let the media/public get a taste, the appetite will become insatiable. The media will suck his youth like a vampire. Look at the media obsession with poor Catherine and this is after she has made herself as boring as possible. Imagine if she actively engaged them, it would be terrifying.
In many ways, it is all or nothing. William needs to keep that firm line no matter how much he is badgered(Hello, Rebecca English!). Leave George as just an obscure, young boy until he is old enough to handle the consequences of being a commodity. Show him the compassion that his father and uncle didn't receive.