Hi Daryl

Im an electrician on the gold coast and i would definately agree with wylie. Adding down lights may be tricky as they look best in simatry. If the excisting light wholes are not in the centre of the room when adding extra D/L they will not look right. Also if you do decide to go with D/L then make sure the electrician knows what he is doing as wholes do need to be drilled (approx 72 – 92mm in size depending what fitting you choose) and there is no room for error.

My advise, depending on the style of ceiling would be: if the house is modern then go with a fitting that has several D/L attached but remeber to get 240v lamps so save cutting larger wholes in the ceiling to fit the transformer or rewiring.
                                                                                                  If the house is more of a classic then nice pendant hanging lights be nice 
                                                                                                  Or for an effective simple look nice oyster lights.

Hope ive help any more questions let me know

Savvy