I'm a KitchenAid mixer fan. I have the basic or classic model, which does what yours does already -- whipping eggs, mixing batters, kneading bread with a dough hook:
http://www.amazon.com/KitchenAid-KSM75-Classic-Tilt-Head-White/dp/B00063ULMI/ref=sr_1_1?ie=UTF8&qid=1410531464&sr=8-1&keywords=kitchenaid+mixer
BUT, that being said, the attachments are wonderful -- I love the pasta maker and the meat grinder, and there's an ice cream maker attachment that I have my eye on.
I've also seen the "Professional" or "Artisan" series in stores -- looks like those have a much bigger bowl and bigger motor, can knead heavier doughs, etc.
Sometimes Williams-Sonoma has sales on certain colors or models of Kitchenaid and sometimes you can also find sales on Amazon. Maybe put it on your list for a Christmas present?