If you can, buy from a dealer near you so that you can take advantage of their classes and service. The sky's the limit on options available. I love my old Bernina and have recently "inherited" a Pfaff 2144 from my dear MIL which does pretty much everything, including embroidery.
You'll have a lot of decisions to make so take your time. You might ask about when they have sales and about machines turned in on a trade-in. People tend to have allegiances to different brands so don't be surprised by those attitudes.
I really love the convenience of needle up/needle down, needle threader, and separate motor for loading the bobbin on my Pfaff. I would definitely want those if I was looking at buying a machine. I haven't had time to learn all the ins and outs or the embroidery stuff yet, but I can't wait.
Good luck on your purchase. You're going to have such fun!