What is your experience with amp power?

I agree that 3 db is quite a bit of difference in sound level and I share your experience with channel balance.  I use to run a Levinson No.32 linestage that allows for 0.1 db changes in volume.  That gradation seemed ridiculously fine.  With most musical sources (i.e., not a steady test signal) it is a bit hard to hear a 1 db change in volume.  But, in terms of channel balance, it was quite easy to hear a 0.2 db change to one channel.  That explains why Levinson offered such small changes.  I don't like stepped attenuators which have so few steps that there is more than a 1 db change between steps--the right volume level always seems to be between the two offered steps.  It is amazing how small is the window on the ideal volume level.  That is another reason why remote control of volume seems essential to me--you cannot, practicably speaking, find the right volume by getting up to manually adjust the volume even if you are not lazy.

bigkidz is correct.

Do not concern yourself with amount of amplifier power, concern yourself with quality of amplifier power.

I bought my amp from a custom builder who also built my preamplifier.  They are "matched" in a way because the amp has input transformers that demand, for optimum performance, being matched to a line stage or preamplifier with a corresponding output transformer.  I had this combination for about five years or so, and in that time, I would sometime be asked how much power the amp put out and I had no idea whatsoever.  When the builder, who is from Italy, came over to the states, I got to talking to him and I asked him about the output power of my amp.  I got such a look of disdain from him; clearly I did not deserve that amp if I concerned myself with such irrelevant and trivial matters.  He thought about it a bit himself and took a guess (I would not expect him to have actually measured it, how it sounds is the only consideration); he guess 5.5 wpc, which is my answer to anyone who asks.

for those worrying about the clear-as-mud, here's a simple solution:

the Marantz 40N amp is simple, has real knobs, and has 75 wpc rated and is enough for almost any reasonable home 

@czarivey What is this 'poor dynamic floor' on high sensitivity speakers to which you object? Never heard that term before.