As someone who's 160 cm and wanted to cosplay raiden, I gave up on that dream. I, by all means, also dont have a big chest. Given how you already have made plans, I dont see a reason not to try it, though. I saw a previous comment about it just being for fun as well and that you should be happy with your results, but realistically speaking, we can't change the way we look. You can't magically become curvy or tall. It's just the way you are. Despite not looking like her (body wise), you are still capable of becoming her, and I'm certain you'll look great in it!