I'd like to suggest that all plantshapes, while maintaining their stats, strengths and weaknesses, have the apparance of their user's totem animal, since that's what happens with all other druid feat-shapeshifts already.
It would greatly benefit Roleplay, in my humble opinion. For instance, I'm considering NOT getting plantshape on my totem druid for he is a serpent charmer, and I'd rather transform into a serpent than a weird vegetable.