M W,
You don't use your treadles .... "treadles that are just for looks". For shame. If you're not gonna use 'em, you need to rehome them.
Otherwise their trauma will cause them to rust and eventually the veneer will peal away. Poor things.
As for the crinkle Kenmore, I have one that is very close to being the best straight stitch machine I have. Very solid, very easy to use, and not fickle at all.
Joe