In the interest of fairness it seems like they're melding a bunch of different significant Batgirl stuff into an origin movie (Year One, Post-Crisis, New 52, Burnside, etc.) so it'll be interesting to see what the final product is. Tonally and characterization-wise I don't think it'll reflect Burnside that much.
It's not meant to look like a high-grade, Superhero, movie costume because it's basically homemade. It's a starter costume.