Watching this topic off and on for a while I notice that Catherine is growing into the styles that suit an occasion. Become confortable with large, medium and small hats; and whomever is styling those hats has found their stride in designing hats that suit Catherine. It's been nice to see the evolution of her hats and headgear and her 'comfortableness' while wearing them. The hats and headpieces become a signature. Nice to see it's evolution.
I also like the way she (or her people) use a range of British milliners, including some more up and coming designers. The quality of her hats, even those I don't like as much, is always impressive
I remember the first few years after she married William and wore pretty much only fascinators. It resulted in a boost of women wearing fascinators to weddings and other formal events. Even today women will talk about finding a fascinator for an event (I'm one of them!), so supporting British millinery is fantastic. Before Kate married into the BRF I think the general consensus in the UK was that headpieces were worn by largely middle-aged to elderly women, yet now women of all ages adorn a headpiece and the right events. I think this is the only time I've realised the so-called 'Kate effect'.