Color Replace tool

Hi all,

I am working on a component that can replace some colours, and I am after a way to improve it.

In the example attached, I am replacing green with light blue, and pink with orange, using Chroma Key TOPs and Composite TOPs.

It seems to be working ok; however, the problem I am experiencing is that the colours I replace are a little bit too “steep”. What I mean is that there’s almost a jump to the replaced colours, instead of fading to it gradually.
If you look at the example and flick through the ramps I am using for testing, I think you will see what I mean.

Any tips to point me in the right direction on how to improve this would be great, or perhaps there’s a better/simpler way altogether of doing this in TD?