I think he wants certain discrete steps without smoothing. But he has problems with intensitiy changes. He said that a change from a deep red to a weak blue is not what he wants. Is it a deep red to a deep blue change what Chico wants? Is he interested in only deep colours?

The link

http://www.colorschemer.com/online.html

shows, that there aren't so many deep colours. If he wants to have 125 colours, then he must also take some of the weak colours and must combine them with the deep colours in a suited way to get a nice looking sequence. What's "nice" to Chico can only he decide, by the way.

I would create a sequence, where the deep red steps to a weak red, then changes to a weak blue and finally steps to a deep blue.

Kai Klaas