To me this is a really disturbing thread......what ever happened to simply walking over to a light switch on the wall or a lamp on a table and....gee, just reaching out and turning the thing on manually? You know, flicking the wall switch, pressing the lamp's switch......????
You could just replace the light-switches so you could do both... rather than the lights themselves which requires you to leave the switch On at all times. Also, anyone that gets water in their basement may appreciate knowing if there's water on the floor because their sump pump has taken a dump, rather than staring at it during rain storms or a snow melt to monitor it.
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Separately to the OP and others. You can use the Echo, couple it to an actual Hub to communicate to things, AND Siri all at once. Some things talk over Wifi, which is where your Homekit comes in (it only does this and Bluetooth LE, exclusively). Others require the Hub. The Echo does both, so you aren't tied down to 1 solution as Wifi talking doesn't "link" it exclusively to 1 thing. Have the Echo talk to the Hub and to Wifi, and Siri talk to the Wifi and Bluetooth LE. Homekit is going to be awesome for door locks... approach your door and it automatically unlocks for you off the BTLE. But the Echo makes more sense for your interior stuff, or garage door - as you can set different triggers for different tasks and do groupings. And right now it looks like the Wink Hub 2 is the best available to partner with an Echo.
You can also pretty much trigger anything with the Echo by running an IFTTT (If-This-Then-That) script as they're officially a supporter of it. Otherwise, as a platform it is more open than the Google alternative - which is shocking.