This new algorithm groups F-Curves into groups of 3-4 with similar colours, since triplets of related settings are more likely to be encountered.
The colours get darker down the list. Blocks of related F-Curves will alternate between being boldly and weakly shaded.
I've left the old method still there but commented out. This new method could still be improved, as some of the colours chosen don't really stand out that well IMO.
Testing and suggestions welcome as always :)
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