Indeed. The Liz Line stretches from Shenfield in the east to Reading in the west. Perhaps "Liz Line stations within 45 minutes", but then you could also include Underground stations such as Hammersmith, Earl's Court and Gloucester Road where there are plenty of hotels.

The fact is that Heathrow already had good transport links which have only been strengthened by the addition of the Liz Line. It's brought a few more hotels into play, but compared to the number already available it's pretty small fry and most people will either end up at something around the Bath Road or at one of the existing offerings.