The sounds of the RT pianos is, in fact, sometimes the issue.
Especially the earlier RTs.
There is sometimes a "wash" of reverb-i-nessthat does not work in some mixes.
The solution to that is to use the MIDI Supertrack instead (most pianos have them).
You get the same performance, but can use whatever piano vst works for you. Easier to fit-in-the-mix.
This is true.... not only for the pianos but especially on the guitars and other instruments as well.
I think PG would be well served to go back and have a good look at all of the real tracks from the early days and perhaps either remove them or better yet, record them again knowing what they now know and using better techniques in the studio. Of course.... if they all translate well into the super midi tracks... using that method might be a good "fix".