I recently bought the little Echo Dot on a special offer. It's small & convenient, as you can take it around anywhere within reach of your wifi. (I take mine to the bathroom.) It has very good play-back characteristics and I use its Bluetooth connection to play through my hifi if I'm in the sitting-room.
As I already have Amazon Prime, I'm able to listen to quite a lot of the Amazon library for free but, for 3.99 monthly, I have access to the entire Amazon Music library, which is vast. This is a special offer where I can only play back on a single Echo dot, but I don't have the need for multiple Echo devices.
I'm certainly not into controlling the lights and the heating through fancy & complicated mechanisms, even though I've had 55 years of computer experience. For the time being, I'll leave all that to the technofreaks who are prepared to pay high prices for the latest gizmos. (My daughter bought a house in Dubai that has this sort of thing. Her system has aged badly & who needs to dim the lights in another room from the kitchen?)