I think the "dream" lathe for anyone depends a lot on
what they like to turn or
would like to turn.
Since I quickly dumped my first lathe almost 25 years ago (the deeply flawed clone of the old Craftsman monotube) and bought a "full sized" lathe, my dream lathe has been the one I see when I turn on the shop lights, whatever it is.
I have little desire to turn big bowls, green wood (too easy), incredible hollow forms - been there, done that. I'd be the worst production turner ever, bored to death after the 2nd piece. I don't turn to sell. Those who love such things might well benefit from one of the amazing lathes available today. I'm am glad others are keeping the lathe makers in business! (I try to keep the tool makers in business)
I love to turn mostly smaller things from dry wood, the harder the wood the better. I love experimenting with form and detail, the more unique the better. I usually make a variety of sketches before I mount wood on the lathe. I never get in a rush. I love doing demos and teaching, especially beginners.
A dream lathe for me is one of sturdy construction that spins with no mechanical slop when I turn it on, has adjustable speed and reverse, will accept all my existing chucks and accessories, and has a sufficiently long bed. I don't need Herculean power since sharp tools and patience can always replace brute force, and arguably with less potential drama.
The Jet1642 I bought in the early 2000s was perfect for me. Building a big stand-alone shop with central heat and air made turning even more enjoyable. Adding a second 1642 helped with teaching and special projects. Replacing one of those Jets with a used PM3520b with a bed extension embedded me firmly in dream land.
And even the most amazing lathe in the world is not much fun without wood. Having a huge supply of dry blanks in adjacent rooms, in a variety of sizes, and of a multitude of species, is beyond priceless.
Life is good.
JKJ