Photoshop: Make Camera Raw features available as an adjustment layer

I know this has been raised in the past and marked as "not planned", but I'd really like to add my vote to the idea of having Camera Raw, or at least some of the features within ACR/LR available within Photoshop as an adjustment layer.

Right now, I can blend a bunch of exposures using layer masks, flatten the image and then do ACR adjustments on that. The trouble is, if I then want to go back and change the blend somehow, I need to discard my flattened layer and ACR adjustments, and then re-do it again. Another option is to do the exposure blend, then import back into Lightroom and do adjustments in there, and then create a new PSD/TIFF to do further PS work.

The trouble with both these options is they are not fully non-destructive. At some point you have to bake your adjustments into a new layer or file. Given that ACR/LR adjustments are just XML instructions on top of an underlying file, why can't we apply these adjustments as an adjustment layer along with curves, colour balance and all the rest?

If it is not possible to do this for some technical reason, it would be great to have ACR's basic sliders available as a global adjustment and the ability to do gradient, radial and brush local adjustments, plus the range masking feature. I'm less bothered about the other Develop panels as PS has enough features to do those functions.