I am not sure of the availability of Maranon in England or if they are a good starter species, but the tinctorius "azureus" would be a good starter.
The top flies are fine, either D. hydei or D. melanogaster. The bottom ones are house flies and I believe they need meat matter to reproduce... Yuck. Go with the fruit flies.
Yes, that is how you are going to keep making cultures.