There are a few aspects that hold it back from being more complex and competitive, namely a lack of card draw and ways to mount a comeback and counter the opponent, but those issues may be alleviated as the game evolves
Even in a depowered deck, you can find Salt Marsh, Jwar Isle Refuge, Frost Marsh, and Secluded Glen to make the other colors in a deck built around The Mimeoplasm or something
Filibuster is a bit harder to replace, but Retether is a great alternative
Her Showcase variant features some stellar artwork and combined with her excellent ability, its enough to sneak her into the list
Deep Gnome Terramancer Deep Gnome Terramancer is going to be an instant mainstay of white Commander decks, and it isnt difficult to see why