Complex sentence: Australia and New Zealand initially favoured the 2011--15 structure, but subsequently warmed to the SARU proposal; a trans-Tasman competition would potentially allow for more regional derbies, fewer time zone complications and less player travel.
Split into simpler sentences: Australia and New Zealand initially favoured the current structure, but the two unions are now reportedly warming to the SARU proposal. A trans-Tasman competition would potentially allow for more regional derbies, fewer time zone complications, and less player travel.