become easier to access
Example: In the last 20 years China has opened up to international trade.
For more meanings of the
phrasal verb open up, follow the link.
To go on to something is to progress.
Example: He went on to university and then became a teacher.
A stepping stone is a stage of achievement or an event that leads on to something else.
Example: Doing a postgraduate honours year is a stepping stone to a PhD.
et cetera; and so on; other things like that
Example: I like driving anything fast - motorbikes, speedboats and that.