@Shortiecanbrawl: No, Captain Syrup is not the same as King K. Rool in context. She has missed out on more mainstream titles then K. Rool has (and comparatively, K. Rool still wins) and when she returned for Wario Land: Shake It!, it was for a supporting role, not as the main villain. Out of the six main titles for both Donkey Kong and Wario, Captain Syrup was only the main antagonist for the first two and a supporting role for the last. King K. Rool in comparison has four role as the main villain and received back lash from fans when he didn't appear in Donkey Kong: Jungle Beat! and Returns. Even if her performance in appearing were as good as K. Rool, she also suffers from Sakurai bias against the Wario Land series, making her appearance very doubtful by itself.
Also, Toad can be clumped into the ones who are recognized when they are part of the Mario series. Toad is almost as well known as the four themselves and was prioritized over Luigi in SM64 and Sunshine, the former of which is one of Nintendo's more influential games. Toad, even with small roles, is still an important character to the series because when you think of Mario, you are going to think of the Mushroom Kingdom and when you do think of the Mushroom Kingdom, one of the very first things that pops up is Toad.