The main power meter view you can see known devices tagged when they turn on and off in real time, but the labels disappear after only a few minutes. There should be a way to keep them around longer for reviewing past data on the main timeline. I find myself looking back a ways and am not sure what is causing certain spikes (I don’t stare at my Sense screen all day). Since Sense keeps track of every device’s past usage, the data exists and would be very easy to enable this. After all, the magic of Sense is that it has found these devices and can show you their usage, and the Power Meter view is the most interesting one to use.
Even keeping the device tags in the Power Meter for just 24hrs would be a huge benefit, a few minutes is simply not enough and makes looking back in the past on the power meter nearly useless.