Flagship product to build around

@ebm 

You're probably on the right track to build around an amp but a Class A/B amp and 350 Watts seems more like a boat anchor than a flagship.

For that money I'd probably go with the Coda #16.  Similar power  but the first 100 watts are Class A (up to 300 watts into 4 OHMS).

I would be hard to build around speakers as I'd hate them until I got something to sufficiently drive them but the amp should be purchased with a speaker in mind.

@ghdprentice 

I'm torn about vinyl.  It does sound better but the hassle involved with cleaning, storing and acquiring the music just makes me question my commitment. to the hobby.  I shudder to think  of having to get up and turn the album over every 15 minutes.  I'm sure I have several hundred albums saved from pre CD era  That would be cool to listen to again but my musical tastes have changed since the 80s and finding excellent copies would be pricey.

IMO, a rock solid amp is the place to start. I have recently swapped my pre-amp and source and have no desire to change the amp. I am (almost) 😀 content with the system. 

@erik_squires 

Regarding room treatment.  Wouldn't the treatment vary depending on the speakers chosen?

@danager  It is a little bit of a chicken and egg question, in absolute terms.  In practical terms my experience has been that getting good room treatment early solves a lot of problems you try to ascribe to speakers, cables and electronics. They help you listen better and you are more satisfied with your choices in the long run. 

The OP was asking about a flagship product to build around and I know of absolutely nothing on earth that helps you build a great system more than having a good sounding room.

You don't necessarily have to pick out 100% of your room treatment before you go looking for speakers, but placing bass traps of the appropriate parameters, diffusors between and behind the listener and some side and ceiling panels is going to get you a lot farther in your audio journey than anything I know.