The inevitable crackles & pops in even the best vinyl always drove me crazy, and I found the distortion & altered frequency response near the center of the record almost as annoying. I have discs that are half-speed mastered and recorded direct-to-disc and both fall short, in my experience. So, needless to say, I prefer a well-mixed or well-remixed CD to vinyl. However, I completely agree that a good amp driving good speakers beats the daylights out of headphones. There's just something about cranking up the volume and actually feeling the music!
I'm #3 & #4, except: #3 is a home-built 486/66 PC with a VGA display, 64MB of RAM and 11GB distributed over two (2) hard drives. Who knows? I may need that parallel-cable, 2-port MIDI interface again someday, not to mention the Cakewalk Pro Audio 9 (which I actually got to work on my Win10 notebook, so maybe not so much); #4 is something that, after many upgrades over many years, I have mostly gotten over. But I definitely obsessively back up everything music-related before any upgrades (which you should do anyway, right?).