Webnick, I think if you consider setting your sights a bit higher (and maybe spending a bit more) than another Adcom - even a more powerful one such as the 565 - you'll be happier in the long run. The speakers you plan to get deserve it. Get the speakers first, then audition some amps, maybe in comparsion to a 565; I don't think you'll be very hard-pressed to find something better. Most audiophiles will allocate at least as much, and often more, to the power amplification than to the speakers. Getting yourself a pair of fairly expensive and revealing speakers, and then trying to power them on the cheap, will rarely work out well - the speakers often wind up highlighting the amp's inadequacies. Listen for yourself and you'll likely agree (and don't neglect trying a speaker cable upgrade at the same time).
You are correct in thinking that you can buy more power for less money going the SS route, although that will not necessarily translate into better sound, or even sound that sounds 'more powerful' - lower-powered tube amps have a habit of exceeding expectations in this area compared to moderately-priced SS amps, so don't get bogged-down in the numbers game of counting rated wpc. Go for quality over quantity.
Bass will usually be more "sharply-defined" with equivalent-quality SS amplification than with tubes. Again, this won't automatically mean 'better' (as in 'more natural') to many listeners, but these things are why you might want to try and hear some tubed amps for yourself before committing, if you can.
To answer your other question, a tubed amp will be turned all the way off when not in use, but it will arrive at fully-warmed-up sooner after being turned on than a SS amp would if it were not on stand-by. Stand-by on preamps is not new, but is more common for SS than for tubes, and running tubes continuously can shorten their life, although so can turning them on and off frequently. Probably most audiophiles turn their tube preamps off when not it use, but there is a large contingent than leaves them on - if you get a tubed pre, you can try this and decide for yourself.
You are correct in thinking that you can buy more power for less money going the SS route, although that will not necessarily translate into better sound, or even sound that sounds 'more powerful' - lower-powered tube amps have a habit of exceeding expectations in this area compared to moderately-priced SS amps, so don't get bogged-down in the numbers game of counting rated wpc. Go for quality over quantity.
Bass will usually be more "sharply-defined" with equivalent-quality SS amplification than with tubes. Again, this won't automatically mean 'better' (as in 'more natural') to many listeners, but these things are why you might want to try and hear some tubed amps for yourself before committing, if you can.
To answer your other question, a tubed amp will be turned all the way off when not in use, but it will arrive at fully-warmed-up sooner after being turned on than a SS amp would if it were not on stand-by. Stand-by on preamps is not new, but is more common for SS than for tubes, and running tubes continuously can shorten their life, although so can turning them on and off frequently. Probably most audiophiles turn their tube preamps off when not it use, but there is a large contingent than leaves them on - if you get a tubed pre, you can try this and decide for yourself.