I love the ability to use the charger and not have to fuss with and Samsung ports, micro USB ports, etc on my phone, which is my primary device

Your phone won't be plugged in, so you won't lose charging ability (or syncing ability) over time due to hardware failures

I guess you could use black electrical tape to cover the acrylic ring so as to eliminate the glow at night, but that would defeat the ability to see that you are connected during daylight hours

No worries as to it having too much power, as any charger will only supply as much power as the phone/device "pulls"