Hi Gilles,
Thanks for the suggestion. Looking at their product offering I see a new shifter, but the 987 seems decent already (room for improvement, but not bad at all), and new cables. I don't feel any slop in the cables, but I can imagine a new set being smoother.
What did catch my eye though is that they have made part of the linkage similar to what I intend to do:
So replacing the rubbery stock part which does allow a lot of movement side to side with a solid part. Easy to make and try, and easy to swap back to stock if it does turn out to be too spartan. Seeing their part being so equal actually makes me confident of this improvement.