Before you buy an Apple TV you can try installing ProjectIvy launcher and see if that suits your needs. It's basically a simplified launcher UI for Android TV devices.
It's not perfect, not if it suits your needs you won't have to buy another device.
That's the one I tried on the Fire Stick, it doesn't always launch, sometimes launches a few minutes after start, and when pressing home it would go back to the default launcher.
I think it's related to the accessibility settings it wants enabled, I was never able to turn it on like it says because the setting just refuses to enable.
It's not perfect, not if it suits your needs you won't have to buy another device.