Even though I don't like Rasa and you can only see part of her face, I think she is good choice for this. It's like how the s/s 09 ads features all plain generic looking models, but it worked and might not have if they had chosen more striking unique models.
Ymre imo has quite a cold aloof kind of beauty that wouldn't really suit the ad. Ymre may have looked more fierce(I know, I hate that word, but it applies) but I don't think the ad calls for that. It has more of a fun feeling to it.