The vintage machines are reliable and great to have. Of course you want a new machine that is all you. I couldn't wait to start sewing on a new machine. There are so many different ones to choose from now. First the features I found I have to have on any new machine are:
Needle up/down
Needle position changeable
automatic thread cutter
knee lift
Adjustable speed control
Excellent Blanket stitch
Assortment of decorative stitches plus Fonts
Drop in bobbin
My favorite machine is a Brother pc 420 which has all these features. It cost me $250. I have Bernina, two Janomes, and a Brother 1500. I use the Brother 1500 for quilting. With your budget you can get two great machines.