To complement the new features of
Simutrans-Experimental, I have been working on a modified version of PakBritain ("PakBritain-Experimental") that makes use of some of the new pakset specific features. I have now released the sources, which are available on Github
here.
At present, there are only a small number of modifications made largely for testing purposes, but, in due course, I plan for this to become a fully-featured branch of PakBritain, and to be released alongside Simutrans-Experimental as its default pakset.
.