Most people think Percy would suit Bart Simpson in Thomas/The Simpsons parodies. They are both young and cheeky. They are both best friends to Thomas and Homer Simpson. Also, Percy played jokes on Gordon and James in Season 2, just like Bart plays jokes on other people in The Simpsons. This is why Percy and Bart Simpson go well together.
If you have more reasons for why Percy would suit Bart Simpson, please add them on this page.