But your question claims that you're using MigLayout. I don't see that you are using MigLayout, because you create a panel which uses MigLayout but then throw it away. So MigLayout is a red herring.
mitchell bat wrote:What would you recommend to use for just one component?
That depends on what the desired behavior is regarding that one component's size and position within its parent container. Without knowing more about that I could only speculate that either FlowLayout or GridBagLayout would be the best choice.