I think your general reaction is correct. The successful sites for freelancers are engaged in a race to the bottom since they are open to and often overwhelmed with offshore developers.
There is plenty of opportunity for new sites to solve this problem in various ways. Specialized skill sets, the ability to do onsite work, training+coding, all provide angles that I believe could be effective, potentially each as the basis for standalone services.
I've contemplated the idea of a marketing site to promote a very specific service:
- 2 Days Onsite: 1 Day Training, 1 Day Hacking with Your Team
- 3 Topics to choose from:
* High Performance Rails,
* Customized ElasticSearch, OR
* Ember.JS-enable your App
No offshore firm could provide this service, and few freelancers tout their most specialized skills effectively.