Responses from fatdaddy2

Help me spend $100,000 on a new system
1. Find a good audio dealer in your area. 2. Pay attention to what he/she/they tell you. 3. Enjoy your new system. (remember: $100K doesn't go as far now as it did when you were young and had better hearing!)  
power cable
Be open to the possibility that the new cable may not perform better than your current cables on either component; just because it seemed like "a deal" doesn't mean that it was one for your system.  
Prima Luna Vs Accupahse
Assume you're talking used Accuphase, since if you can't afford a $10K speaker you can't afford a new Accuphase either.  
My High End Audio Gear As A Long Term Investment!!!
Investment? Not hardly.  
Warm Up Time/Cost of Operation
Luxman Class A owner here, 400 watt dissipation when on. Usually allow 30 min warm-up; leave on most of the day on weekends.  Keeps the room nice and warm during the winter.  
Rel t9x or Rythmik F12G
Amazing how someone can state "already overpowering the room" without any evidence.  I'm currently using a REL S510, located in my room's primary bass node, which is located right next to my seating position.  Completely invisible with my Forte IV... 
New Speaker advice
At this point, forget the measurements and use your ears.  Except for the MoFi, the designs are all fairly similar, and it should come down to preference.  
Better hearing
Not likely, but perhaps your perception has changed.  
speakers for small room
Klipsch Forte IV or Cornwall IV.  Work great with sub, very dynamic, work well as near-field speakers when necessary for small room.  
Question about suitable fuse metals
Burn baby burn! Disco inferno! (it only takes once...)  
3.2 Channel with upgraded L/R or 5.2 channel?
Unless you've got a humongous room, those REL 212s already have your room well-pressurized with bass energy; adding more subs would primarily increase ambience, so you don't need to go big to get the job done.  Echo the recommendations regarding t... 
Service After the Sale
Definitely first-world "problems".  
Why Can't Modern Tube Manufacturers Make a Proper Tube?
Hmmm.  Maybe because it's a tiny niche market and there's no profit in it?  
My history with treble.
Hmm.  The one thing I don't see mentioned, especially if you are old enough to have been auditioning equipment in the 1970's: when was the last time you had your hearing professionally checked? Obsessing over treble response in equipment doesn't m... 
SET Lovers, what's the one solid state amp you love(d)?
Luxman 580AXII