CoHere, a Coworking space located in northern Colorado, in the United States, wrote this post regarding what a regular coworking space should not lack.
Here is a list of five key elements : 
1. Comfort and Ambiance
(…) Fluorescent lights, worn out desk chairs and stark white walls belong in hospitals, not your everyday workspace (…)
2. Multiple Workspaces
(…) Do you have to fight off other early risers for the “good desk”? (…)
3. Conference Space
(…) Freelancers and small business owners are constantly having meetings. Lots of them (…)
4. Multiple Membership Plans
(…) The whole reason people are attracted to the idea of freelancing or owning their own business is because they feel trapped in the traditional 9 – 5 (…)
5. Good People!
(…) Find out how large the membership is, what kind of work the other members do, and ask the space owner/host/curator which days tend to be busy or empty (…)
Read the full article here