1. GWA is not an industrial, it is a service provider which relies on B2B sales and consequently needs to take its branding seriously.
1. Look at SSR and QUBE, no-one cares that they have liveries from all over the place. The livery isn't an important feature of their business like it is for retail transport like say airlines.
They do, however, have at least a small portion of the fleet fully up to date in the current livery and take steps to ensure those vehicles are nice and spiffy when they need to have publicity photos/videos done or for major announcements.
All the other operators in Australia are the same, including GWA themselves who have their modern locos in the current livery and the older stuff in a variety of former liveries including some decrepit junk still in AN green. Even before they had the modern classes (GWA, GWN and GWU) delivered, they always had some of their older fleet kept up to date.
If/when GWA is renamed to something else, I'm sure that they will be exactly the same - part of the fleet in the new branding for the announcement and for publicity photos, and the rest left in the old colours to be repainted when they are next scheduled to go into the workshop anyway.
First impressions do matter when it comes to selling B2B services. If two companies offer pretty well the same services at the same price, the one which makes a bit of effort to impress the client has a competitive advantage. That's why big companies have corporate boxes at the footy (it's for entertaining clients, staff only get to use leftover tickets) and advertise on mainstream media in time slots which have better than normal proportions of executives and directors viewing (e.g. BHP saturating the recent Tour de France TV coverage).
Anyway, the big issue is about changing the name of the company - something never done lightly or hastily - rather than any rail operator's spiffy/scruffy loco ratio.
GWA is actually an Australian company (Genesee & Wyoming Australia Pty Ltd) and not just a division of a US company. Once Macquarie own the business, they will own the name. If Brookfield-owned GWI want to take the G&W name out of circulation in Australia, they need to propose a deal which will be to the satisfaction of Macquarie-owned GWA.
An acceptable deal for Macquarie-owned GWA would be something along the lines of voluntarily renaming itself to something else within a year or so, in return for Brookfield-owned GWI agreeing that any further entry to the Australian market would use a name other than G&W.