Going solo is very enjoyable, you can do what you want to do when you want to do it. What to skip space mountain and ride on the people mover a few times and relax - you can. Want to take pictures, sit on a bench and people watch - you can do that too! I am pretty social, so I talked to others in line and actually met a few people eating and neighboring tables, I guess that is one advantage of tables being close together.
Advantages: You can do what you want to do, you are more efficient since you leave when you are done eating, you the bathroom when you want to go and there is not arguing about what to do next.
Disadvantages: Wanting a drink while waiting for a parade, or need to get up to use the bathroom / get a drink refill while eating since there is no one to watch your table/place/stuff.