I have been working with several charities lately and am collecting insights on governance for such organisations.
In Ireland the state of online development in the charitable sector is mixed. It ranges from the very sophisticated to the quite basic.
In terms of governance support, the best setup I have seen consisted of a Web manager + 2 developers + 1 designer + 1 editor + 2 content writers. Not bad if you can get it (& if you resource it properly)!
However, my research also shows that many sites are managed by 1 person with a broad range of responsibilities. Inevitably, such people are badly overstretched. The result is that online potential is not maximised.
This is especially so given the emergence of extra online assets that also require management, e.g. Facebook, Twitter.
In the UK, I am aware of charities such as
Oxfam with a web team of +/-30 people. Indeed, I believe the cancer charity
Macmillan has 4 people
solely responsible for social media.