Pretty much from a collectible point of view none of these stand out. Given a choice the only one I'd be interested in is the 237. It's said to have the best satin stitch of any Singer and an added plus is it can be treadled. Lot's of quilters use this machine.
The Touch N Sews have a small following but they're not really worth anything. People either love them or hate them.
The Athena isn't really an embroidery machine. It has some fancy stitches that can be used for what you can call embroidery. According to every Singer OSMG I've ever seen have something to say about them, they were junk right from the start. Same with the Futuras.
Cari