No you are not a bad person, just average.
Okay first question I have is how low power do you really need. You have a solar cell, so you have power during the day, is IDLE a deep enough sleep to allow the battery to be charged? It seems it ought to be enough to me, but I do not have your energy budget in hand to be certain. Why push the edge when you probably have more energy than you need while the sun is out. Backporting Hans low power mode seems like a quick easy way to go to minimal power, but before you try to do more than that I would be certain you need to do more.
At night I can see wanting to idle more, to prolong battery, but you need the timers on so you can’t go much below idle and still have them. Unless the watchdog can be configured to the period you need for timers. (This sounds like alot of work, so I am not sure it makes sense.) The rfbee in low power will save you some power as well, but you may need to send command a few times to be sure that they take. On the other hand with the LED on you are almost noise in the power calculations, or so it seems to me. Hans said he had low power down to ~18 mAs, that is not great, but it is very little compared to a bright LED. 3.3 * .018 = .06 Watts so If you have a 1/2W to a 1W solar cell, it is hard to see why you need a lower sleep level during the day.