Ok, I'm going to have some excessive fun here...
If cost was no object, I would have four major systems. Of course, each would be used in an acoustically great room of appropriate size to the system, and each would have separate functions:
1 - Ultimate 2-channel: My goal here is to have a 2-channel setup that can produce music on a grand scale; I would want the system to be able to recreate a live symphonic orchestral recording as if I was sitting in the first 10 rows of Carnegie Hall. Based on equipment I've heard in various situations, I see this system to include Halcro monoblocks and preamp, DAC by Meitner. Speakers are a hard choice, because I've only had limited exposure to speakers that can produce music on this scale...but based on what I heard at CES last month, I'd say the JMLabs Nova Utopias might be a good place to start.
2 - Ultimate Home Theater: I'll be honest here; I'm not a complete nut when it comes to movie soundtracks. At the end of the day, I'm watching the movie and being engrossed by the story...I just want the sound to be non-fatiguing. In the "cost is no object" arena, I'm probably looking at a Wilson Watt7 five-channel setup...not sure that I'd look at the Wilsons for a music setup, but for speed/dynamics that home theaters might require, I think they'd be good in this application. As far as amps, processors, etc., call me crazy, but I think I'd go with a full reference Mark Levinson setup. It does what it needs to do, and the user interface on the pre/pro is excellent. Of course, given my lack of "enthusiasm" for such a home theater experience, I think this would be the last system I spent a ton of money on. A more realistic setup for me would be a Sunfire home theater setup using a Sony DVD/SACD player and Focus Audio speakers.
3 - Second 2-channel setup: This might sound self-serving (and possibly might get removed because of my status as a dealer), but my second 2-channel setup would not necessarily strive for the ultimate in realism and transparency like my "ultimate 2-channel system" does. I am a firm believer that unless you go for the ultimate and spend tons and tons of money, you are generally going to get systems that have certain colorations and characteristics that you really like/dislike. It's in these kinds of systems that I really love to listen to "smaller music"...jazz, quartets, blues, vocals, etc. For me, I became a dealer for the equipment I own for myself, because I am a big fan of the particular sound the products put out. So...my second system 2-channel setup would be a reference-level version of the equipment I currently own: Blue Circle AG3000/AG8000 preamp-amp setup, Focus Audio Master II speakers. As far as digital source, instead of the Resolution Audio Opus 21, I might match this system up with the Dodson DA-218 DAC.
4 - Third 2-channel setup: This would be my "esoteric" system. It would be based around the Rethm single-driver speakers I heard at CES. Would drive them with some low powered SET amps...probably something like Antique Sound Labs...and a turntable from Basis or SME (I know relatively little about turntables, so stuff like what cartridge/tonearm etc I have no idea).
And of course, if money was no object, I change every system every year...!
And yes, I would also have a room dedicated for live performances...