Hi, KiK, and welcome to the Board. You are obviously one talented guy with an eye for gorgeous machines. The bikes and the Singer you posted are beautiful. I especially love the cranapple red bike.
My greatgrandfather was a skilled upholsterer who made custom seat covers for buggies in the 1800s, and then transitioned to car upholstery when the Model A came along. He passed his love and gift for sewing to his daughter (my grandmother) who passed it to my uncle and some aunts, and now to me and my sister. We each own one of Grandma's machines.
You will find that bikes have brakes, but this vintage machine collecting thing does not. Or at least the brakes are prone to failure! Whenever I'm tempted to buy another one, my internal "check engine light" comes on. (So far I have 4 vintage and 3 modern machines.)
Please try to make something with a machine and show us.