Heat a grill pan over medium-high heat. Grill the corn until lightly charred on all sides, about 10 minutes. Set aside to cool slightly, then cut off the kernels and reserve.
Heat the oil in a large saute pan over medium heat. Add the onion and sweat until translucent, about 5 minutes. Add the garlic and cook for another minute. Add the lima beans and tomatoes and cook until tender, about 5 minutes.
Add the reserved corn to the saute pan. In a small bowl, mix together the butter and mayonnaise. Add the mixture to the succotash along with the lime juice. Season with salt and pepper. Transfer to serving bowl.
Sprinkle with the basil, Pecorino-Romano, cilantro, mint and smoked paprika.