I’ve got a Last Coal which produces these pretty graphs:
http://linkagedesign.blogspot.com/2015/11/last-bikes-coal-275-2016.html
And the leverage ratio is what I’m looking at as I’m considering going from CCDB Air to a CCDB coil (inline)

And although I can clearly see the progressive nature in the second half of the travel should go well with coil as I want a more linear action, what about how it goes regressive at the start, and ends at below 2:1?

The Marin mount vision has similar leverage ratio and this article seems to discuss some issues with a curve like that:
https://www.pinkbike.com/news/behind-the-numbers-marin-mount-vision-suspension-analysis.html

Anyone have any input?

Should work well if it fits. The leverage curve and the rocker link design look well suited to a coil.

The initially regressive portion of the stroke will mean the coil will feel like it’s wallowing a little at the beginning of the stroke compared to a typical air sprung shock. But I guess it’ll allow you to use more of the travel more of the time potentially, that sub 2:1 end stroke makes the bike highly progressive, and I suspect with an air shock fitted, you’ve got to be hitting some pretty big drops to achieve full travel unless you’re running way too much sag in the first place…

Must say, the curve surprises me, considering ostensibly it’s just a single pivot with a linkage actuated shock, much like my Evil Offering, and here’s the curve for that…

vs yours…

🤔