The truth is that all kinds of people can become adopters. There is simply no ideal type. Each agency will be looking for people from all kinds of backgrounds and with a variety of life experiences to meet the needs of the children in their care.
Your personal circumstances, may limit the sort of children who you will be approved to take on.

However, the Government appears to be keen to stamp out the practice of different agencies having different policies on who and who not to approve.
Instead it seems likely that national criteria will be introduced which may make becoming an adopter slightly easier for some people. Exactly who will benefit remains to be seen.