I'm not sure if this is the right place or not to post this but I would really like to see a feature where if for example you added a layer with a solid colour on it and made it into a keyframe, then you duplicated it and turn the opacity down by 20% it would be 20% lighter on the new frame but still 100% on the first frame. This would be useful for smoothly animating lighting/glowing effects or blushing but proves to be quite difficult doing it manually by brush or very bulky if doing it layer by layer in folders.

Our current plans for animation include something fairly similar.

We intend to allow animating layer opacity as a separate set of keyframes on their own channel. Eventually we may also include options for interpolating between the opacities. There's plenty to get through on our todo lists before we get quite that far, though.

Sorry for not replying sooner.

Thank you for taking the time to reply. I look forward to seeing all the things Krita plans to add to the animation feature.