Rosita is my favorite recent Muppet, too...with her talents and speech pattern, I imagine her as the monster equivalent of an older child (7 or 8 years, maybe?). Her wings were kept, though, for at least a season after she stopped flying; I remember an episode where Maria cheers her up by helping Rosita count other things her wings could do. (The list ends with Rosita herself discovering one last use: she hugs Maria as the closing theme plays.)
Rosita's fondness for hugs also won me over; I couldn't help saying AWWWW! when her familia appeared in the Spanish Word of the Day segment and began group-hugging. She also did a segment which taught the word abrazo ("hug") itself...hugging that over-excitable elephant, of all possible characters.