We haven’t used subdomains for the different parts of the website, we simply tag it at the end of our URL. So: www.domain.com/blog or www.domain.com/case-studies
I like the idea of using subdomains for it, though and the way you’re using it makes most sense. I wouldn’t complicate the naming scheme just to be a little different. If I was visiting your domain and I know that you’re using something so straightforward, it would make most sense to me rather than things like: ourteam.domain.com or letsgo.domain.com
Even though they are ‘hip’ it doesn’t always make sense to sacrifice simplicity for the sake of branding.