I know what you mean about there not being much change in "ambience"between standard and first compared to the Mk3 stock. Some wood effect panelling and a different colour scheme to soften it up would make a difference.I have to say that it's certainly a step change versus what has come before it and the old stock that it has replaced, although I would say there is not quite the same feeling of a difference in standard from first class to second class like there was on the older stock. I like them for what they do and certainly enjoy traveling on them.
But really I'm nit picking. They are much better than what went before. It is at least possible to work on a laptop comfortably. This was impossible on the Mk3 stock due to the seats being permanently in the fully reclined position.
Overall the 745s offer a much more comfortable and pleasant journey than what they replaced.
I do miss the distinctive sound of a slam door though.