I've got a rather large Dracaena Marg. houseplant. It has three large
stems rooted in the compost and these stems are trimmed so that
another three stems emerge at the top. These stems have become quite
long and leggy and I'm not sure what to do.

Should I trim them back and repot the whole plant, or can I make a
whole new plant by cutting the main stems and repotting?

Will these stems root easily and could I re-create the original plant
arrangement without too much trouble? I'd like to have a go.

Many thanks for any advice.