The way you have the volume sends to the monitors and the monitor levels set sounds fine. If they're both halfway up and the volume you're getting in your room is loud enough for general mixing with a little bit more beef supplied by turning up the send to the monitors when you really need to crank up the volume for a minute or so then all is good.
The problem with having the monitors permanently on and powering them with a main switch is that the repeated sudden surge of electricity into the speaker may shorten the life of something inside the unit if it is designed with a soft power-up using the speaker's own switch. (someone with more knowledge of circuitry and power supply design may be able to step in here to help out)
I don't suffer from insanity; I enjoy every minute of it.