Moqette with some leather trim, like what Transdev, Trent Barton and Go North East do would be my preference - you still get the well established benefits of fabric, but with the alleged premium element of leather.
Leather looks awful when it’s aged and you tend to slide off the seats, bear in mind in FirstGroup some seats won’t be reupholstered for 10/15 years if at all.
Regarding the fact new and refurbishments aren’t currently aligned, I’m guessing new deliveries are decided by head office, and they still tow the E-leather line unless someone gives a strong opinion to do otherwise (and we know some MDs do this, whereas others are just on a corporate career ladder) whereas refurbishments are decided at local level?