Mae rhan o’r ymateb hwn yn cynnwys cyhoeddi uchelgeisiau a chynigion sy’n rhoi amlinelliad o’u huchelgais ar gyfer y gwasanaethau rheilffordd.  Byddai’r rhain yn golygu uwchraddio sylweddol ar Brif Reilffordd De Cymru o ran capasiti, cyflymder y trenau, cerbydau a thrydaneiddio dros ardal eang – gan arwain at welliannau megis amser y daith rhwng Caerdydd a Bristol Temple Meads yn 35 munud a Chaerdydd i Lundain mewn 85 munud.
Part of this response includes the publication of aspirations and proposals that outline its ambition for rail services. These would see a major upgrade of the south Wales main line in terms of capacity, line speed, rolling stock and widespread electrification – leading to improvements such as journey times of Cardiff to Bristol Temple Meads in 35 minutes and Cardiff to London in 85 minutes.