nice background and atmosphere (and so romantic :) )
but I think the vector that you've used doesn't quite fit into the setting yet, because everything else is
semi-dark, while Lacus is really light. Also, she has that anime vectored style (with cell shading) while the background
is photographic with realistic shading. Either darken her a bit and give her some shading (because it looks like
she's standing in the shade under the trees), or, you can have a sort of spotlight on her, like coming from a
skylight or something. Also, Lacus needs some shading under her feet to make her look like she's standing there
instead of floating in space.
the petals also look vector-ish. while it matches Lacus, it doesn't quite fit with the photo-like background.
Either make them more realistic, or make the background images more abstract and anime-ish (esp those columns.
anyway, it's well-put together, just needs some tweaking to make it perfect :)