I will preface this post by saying that I know I am not a design specialist - I'm just spitballing here. Take what you will from this post!
As much as I would love to see the "old" NSE and InterCity liveries return, I appreciate that BR would have updated them at least once since those days, and an updated version would be nice. There's nothing wrong with acknowledging the past and using some of its best design cues to inspire modern designs.
I am very much in favour of standardising as much as possible. But I do think there should be variations. I'm in favour of the "three variations" that SWT had - one recognisable livery but variations. However, I do think there should be variations for the nations. Therefore, from largest scope to smallest:
- CrossCountry. This needs to have the flagship livery - the one that represents GBR the best. I would love to see a modern variation of InterCity Swallow; like LNER have done.
- Long distance services (SWR white). Similar to flagship but different enough to differentiate it.
- Medium distance services (SWR blue). Perhaps same design as long distance but in different colours.
- Short distance / metro services (SWR red). As above; same design but different colours.
The livery should be designed in such a way that:
- National/city variations can be catered for.
- Nameplates can be mounted and not look out of place.
- Spaces can be made for regionalised text.
So for example, you could have a long distance train, with a "City of Oxford" nameplate, a silhouette of the Oxford skyline, and the Oxford coat of arms on the side of the leading carriage. None of this would be in big bold colours - it's not a would detract from the livery; it would rather enhance it. To give some idea of what I'm thinking of, consider Virgin Trains' NRM 40 year livery, or their X-Men liveries. Still clearly Virgin Trains but with a clear extra message. Also consider the Battle of Britain Memorial Flight livery that went on a 91.
In Wales, you could could have the Welsh flag placed on the leading end of the carriage, similar to how depot badges are sometimes placed, but larger. Or, have a much larger but opaque flag that takes up much more of the carriage. You wouldn't have to have this on EVERY train in Wales, just a handful, or maybe the first of each class of train.
Another approach could be very minimalistic - consider SWT's first livery on the 442s, where they put the unit number above the orange stripe. (There's a picture
here). Use that space for the personalisation:
"Great British Railways" at the leading end of the carriage (assuming it's an end carriage) then "Visit Oxford", then a smaller vinyl silhouette of the skyline. Small, doesn't detract from the main livery but it's a nice little hint of customisation.
If I was a graphic artist, I would do a couple of mock-ups... whatever happened to that website that had a load of photoshopped liveries?