Actually, I will offer a varying opinion - I think the Contemporary would be fine for a solo.

I stayed there last January with family. MK is an easy walk. You can rent boats as a solo, which is always fun (in my opinion!). Also the hotel has the Food and Fun Center, which is a food court, which some solo's find easier than sit-down restaurants. The room size is very nice, too. There are interior corridors in the garden wings, though to get to the tower you must walk outside for a little way. I always saw plenty of people around, and felt quite safe.
I have taken many solo trips, and I stayed once in the Epcot area, at Beach Club. I liked it, but Beach/Yatch Club has no food court, which I found very annoying. There was nowhere real close for an early quick bite to eat, or a late night dinner/snack. I usually don't go to sit-down restaurants as a solo, but I did eat solo at Beaches and Cream at the counter. It was nice, but I prefer a food court being at least available. I remember eating snacks many times in my room, since I couldn't get a meal.
Oh well! I would happily stay at the Contemporary solo!
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