Wow Peace, that's a number of biguns. The most important social issues I think would vary a lot by the location of whose talking. So where I am the social issues are health and premature death, unemployment and underachievment amoung young people and how to cope with these to assist the survival of former industrial towns and villages. I also have an idea that this might be true for other communites in other areas of Wales.
One reason why south Wales might be treated seperately in some histories is that it is urban, (post) industrial and English speaking.It also has the majority of the population. The process by which the eastern valleys of the coalfield lost the Welsh language is both complex and painful, and I think that it caused real rifts within Welsh culure and nation which are still very problematical. Which brings to folksongs and history...One of the major products of south Wales is historians! Its taken very seriously