I've had several crock pots through my life, have bought cook books specific for crock pots, have had various sizes, tried various recipes and can honestly say, that I/we haven't liked anything cooked in them. It seems to us that it doesn't seem to matter what kind of meat, spices, veggies, etc., that you put together, they all taste the same--blah. I know others that absolutely love them, but personally, I'll do without one.
Since it's just you, if you want to try one, I would go with a small one and see how you like it, then if you like it, you can either be satisfied with that size or get one bigger. On the other hand, if you don't like it, then you haven't spent a lot of money on one.