DH and I were talking about that. I would be hard pressed to give up my Janome 6500 or Janome Jem. The Janome 6500 is big and heavy but I can still take it to class, has many stitches, walking foot, knee lifter, free motion foot, large opening, automatic threader, sews great, quilts great, no tension issues, table that attaches, automatic cutter, needle up and down option etc.
Most of my vintage machines are straight stitch only or at best zig zag. Many have no reverse. Don't get me wrong I really like sewing on them but I like the features on my Janome too.
It would be limiting to have only a Feather Weight or singer 201. Even a Singer 401 with all the cams would be too heavy to move around or take along and boy do I miss the automatic threader especially since I am just starting to get older eye issues. If I had to choose it would probably be the Bernina 830 as it has the knee lift, is lite enough to carry, is all mechanical metal parts. Right now I am piecing on a Feather weight and quilting on the Janome 6500.
I told DH I was not selling any. I like them all!