Once you start on a manufacturer's website and see the progression of features that differentiate the machines, the rest of the sites will become easier. You might start listing the features that are beyond your Kenmore and start reading about them. Some will seem more important than others and will help you figure out what machines to try. Are you likely to want to do machine embroidery? That may help you, too. I'm not a fan of it, myself, but if I were, I'd be looking for the ones that do it best and sorting through them. If you have any physical limitations or see one coming down the road, there may be features that zoom to the top of the list. A lot of things that are comfortable to do for 10 minutes can become a major pain if you spend an afternoon at it.
Hugs,
Charlotte