Then they could at least provide more than one option. Though while far from perfect, one of the things I like about Alexa/Echo more than the ability to change it, is that with multiple devices you will generally only trigger one (the others within earshot will listen and then ignore it once one of them has picked it up; works well in my house at least apart from one place where echo/reflection sometimes causes one in another room to get preference, but even then only one device usually triggers). Sounds like that was the main problem for GP.
Most of the time I can just turn in the general direction of the device I want to "listen".