I do and always have ridden in any weather (except hail and snow).

Has anyone found any methods to reduce the RT's tendency to aquaplane?

The weather was rainy so I took the day off and spent it on a 700km ride to do a little testing with settings to reduce aquaplaning. These seemed to help
  1. Putting the suspension firmness up.
  2. Which in turn put more weight on the front wheels.
  3. Later I added 1 PSI to the front tyres and this too "seemed" reduce the tendency to aquaplane.

When I rode two wheel tourers, if it was light rain we'd keep suspension soft so that the tyre didn't get too pushed around, allowing it to just softly follow deformations in the road surface. If the rain increased to the point of pooling on the road we'd increase suspension pressures to help apply more force to the tyre when it met pooled water by the suspension wanting to push the wheel downwards more readily.

Have you found any aftermarket tyres that have provided a noticeable reduction in this behavior?
Have you found any aftermarket suspension that have provided a noticeable reduction in this behavior?