The problem I have with Padme (just gonna refer to Anakin's wife as Padme for simplicity's sake) not playing a big role in the story is that there needs to be a strong female character to offset the almost too large as it is male character lineup. Could you imagine Star Wars without Leia? Harry Potter without Hermione? Indiana Jones without... well any of his various women except Willie Scott? It's a story necessity. Especially if you're working off of Joseph Campbell's Hero's Journey, which I am, as Joseph Campbell was a huge influence on Star Wars. There needs to be a "godess" or "temptress," and yes, these archetypes don't have to be personified, but they really should be in the Star Wars universe, as it really is a fairytale in the simplest sense.