I started putting this system together in 1995 and have been adding things very slowly ever since. I've learned through the years that matching all the components and cables are one of the most important things to achieving good sound. I welcome all comments & opinions as Audiogon has been a great expierience for me meeting so many great people and sharing information.
Acurus Amp/Preamp sounds quite good. Fast & punchy, as are the Speakers. MIT cabling smoothes it out a bit for a pretty good balance. I live in the Sierra Nevada Mountains in Eastern California near Yosemite. The plants/Greenery does seem to help the sound, it is a subtle improvement as you guessed, but a good-looking way to improve my situation.
The Genesis Servo 12 Sub has adjustable High and Low pass filters and adjustable crossover (set at 47hz currently) and adjustable Phase Control so it is pretty flexible. However, It is always difficult to get a 12' driver to mate perfectly with 5 1/4" drivers, so there is a little bit of a trade off to get that deep bass.