I find around 50% of the tyres range gives me the sweet spot just before the road buzz increases badly.
Trykers 40-406 have a 55-85 psi range and I like to run them at around 70 psi.
With the medium elastomer in the front suspension of my ICE Sprint I can run the tyres around 10 psi higher for the same feel as a non-suspension front end.
With the hard elastomers it's only around 5 psi higher.