Having a temperate controlled kettle has greatly improved my tea enjoyment. Not just for more sensitive tea types, such as greens, but for all tea types.
When I started my journey with tea, I primarily drank black tea. I believed that I just didn't enjoy green tea and even many of the black teas that I was trying. It turns out that I was not only over-steeping them, but also negatively affecting the balance of the profile by only using boiling water. I have since learned that some teas need a lower temperature to be in balance. Temperature control has enabled me to experience all tea types at varying temps, tweaking the balance and profile to get that perfect cup. I have found more complex and enjoyable profiles in teas that I thought were simple and harsh.
I know that temperate control is not for everyone, either due to differing preparation methods making it not necessary or maybe you are better than me at getting the temperature right on your own. For me, my kettle is my most important teaware. I'd gladly give up all other teaware to keep it.
My kettle
I have the kettle shown as the image of this post. You can find it by searching "temperate controlled goose-neck kettle" on Amazon. It must be a generic, as it has gone by multiple manufacturer names. I have 2 of these, one at home and one at work. After a few years with them, I am still happy. It is a cheaper kettle, but it still has all of the features that I want. My only complaint is that I wish it held more water, so I didn't have to refill as often.