My favorite features are - needle up/down, automatic threader and cutter, and automatic pivot feature. This allows you to come right up on a pin - the pressure foot raises automatically when you stop sewing - remove the pin (or adjust the fabric) - and the foot lowers again when you give it power. I would not be without this feature. The Babylocks and Brothers have this at the most reasonable prices.
Additionally, I prefer to have a nice blanket stitch, as I love to do appliqué.
Now, if they would just add the IDT system (no need to use a walking foot), they would have every feature a quilter would ever need....(this made Pfaff famous).
Goot luck with your decision. Let us know what you end up with.