But Sudowoodo is an imitation of a tree. Not a Trevanant. You should also advertise how fun Colosseum was and how these Pokemon appeared in Gen 4. They just aren't Pokemon with good stats or aren't evolved so they aren't used.
The one's I agree with would be Remoraid and possibly HootHoot, but the rest are such lovely Pokemon that are pretty well remembered, especially Brock's Sudowoodo