Well flowery, yes, impressions do count, but being articulate and relaxed is essential in a creative job.
I can understand the OPs dilemma, coming from a more straight laced environment, but really she should let her work do the talking.
If she's going to be in a financial job in the company she should dress like that.
If she's going to be on the design team, then a dress with a statement necklace would do the trick.
I've interviewed a lot of people in the past and after checking they could do the work, and wanted to do it, we always chose the ones who were team players, willing to clean the loos after themselves, and weren't too up themselves about their appearance.
The one person who we employed who was a bad fit wore a matchy-matchy suit - she had come from a big state organisation and thought she was too special and senior to wash the mugs. She went after her probation was up. Mutual decision. She was in to do admin, and in the end I hired a back to the workforce 40 something mum of two teens who was superbly organised and multi taking in her stead. She dressed conservatively, but washed the mugs.
We had 100% creative people who wore bomber jackets and combats, and guys who wore glow stick necklaces, with Mohawks, but most of the staff had mixed roles, creative and also including sales, and wore a more transferable garb, that wouldn't frighten clients.
They were hired on the basis of their past work, skills and experience in various technologies. I never made a decision based on what someone was wearing, rather what they brought to the table, and whether they could muck in.
I think the OPs friend should stop worrying about her clothes, and concentrate on her portfolio, and her work.
Important as appearances go, let's not forget that she's there to work, not pose about being 'uber cool and creative', and looking like a catalogue mannequin, bringing nothing to the business.
I wish her good luck!