Bike handling includes not only the suspension parts, but the chassis too. The small Honda's have pretty flexible chassis. That is why stiffer forks and varying the trail and rake don;t always have the effect someone would think they have. Small amounts of stiffening can have some positive effects, but large changes (like fork swaps) can change the nature of the bike. The steering neck in particular can move quite a bit dynamically. A flexible fork can absorb or reduce the effects. When you get a significantly stiffer fork, the flexible chassis can actually add steering inouts, creating an unstable ride.
This is not guaranteed, and the effect will vary by bike, but to really improve handling, significant chassis and fork and suspension changes need to be made. Not saying some mods aren't successful, just that there are a lot of unintended consequences to significant chassis changes....
If you look at good handling bikes, they are more than just a stiff fork. The chassis is designed to be stiff where it needs, and flexible where it needs. To stiff can cause stress fractures, too loose can cause wobbles. Ducati's tend to be good handling. the trellis frame is stiff, the motor is a part of the stressed frame...The components are made to work together. putting a Ducati Fork n my CB360 would not really improve anything as the steering neck and backbone can flex way more than the the Ducati neck.
That's why most chassis mods done by "ordinary" people are for looks, and most often, are detrimental to the safety and handling of the bike.
It is like the 454 Chevy motor put in a Chevy Vega. Looks impressive. Even with he front end reinforced, the first race the whole chassis twisted. The vega was not designed to withstand the forces a huge HP motor can put on it.