Smooth edges for "Auto Eraser" (similar to "Color to Transparency")

[shijan]

Auto Eraser is a smart and quick tool, but it only produce hard edges. Is it possible to add small checkbox in tool settings so it behave same as Color to Transparency tool and produce soft smooth edges based on color?

Current closest option is Color to Transparency + layer mask. But this is rather limited workflow because it can pick only one single color per filter layer. Same time Brush can pick one color per every painting stroke.

Color to Transparency Brush may look like tiny improvement but in reality it could advance things like hair masking or separating semi-transparent objects like clouds or glass objects from mixed color backgrounds to the level of very special expensive plugins.
Maybe it could be not just improved Auto Eraser, but new separate Color to Transparency Brush tool?
Already send this request to developers, but just want to know what other people think about this...

[shijan]

Another possible option is use "Color to Transparency" in Filter Brush Tool. But in this case things may be not so fast and easy because every stroke across background of different color will need new manual color picking.

If imagine design of this tool in even more advanced way, it can use lists of preselected multiple colors from "Keep" and "Drop" lists. Similar to legacy onOne Mask Pro plugin described in this video https://www.youtube.com/watch?v=1LKBY8JpqWk

[shijan]

Also formally "Color to Transparency" could be emulated with "Replace Color" brush, but as it was recently noticed in another thread https://www.pl32.com/forum3/viewtopic.php?f=1&t=6790 , it can't paint with transparency.