There are several remotes to handle what you are looking for. The best value would be an MX-900. The button layout is very nice and it is highly functional. I don't know if your Panasonic uses "play" as a power on command - many DVD players do. That's a possible workaround for discrete power. The cable box also does not have a discrete power command, but that is usually solved by leaving it powered on. There is usually no additional power consumption by leaving it on.
If you want nothing less than a remote system to sense if a component is on or not, it becomes a little more involved. Either a URC remote (like the MX-900) with a MSC-400 and sensors, or an RTI remote system with a RP6 and sensors. Either of those will handle power for your components without discrete powr commands.
Please feel free to e-mail or call if you have any questions. I would be happy to help you.
Thank you,
Damon DG
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