Okay so I have seen these posts:

viewtopic.php?f=288&t=125456
viewtopic.php?f=156&t=121581

And have seen that realistic watercolour is something that is to difficult to implement into Krita.
However while looking for various drawing apps for android I found this little gem:
https://play.google.com/store/apps/deta ... nter&hl=en

What I have found seems as though it might be something that could help immensely with watercolour emulation.
And that is the following:
http://sta.sh/012en8nbyzsy

As you can see as the brush moves along, the previous parts of the line slowly start to widen, similar to how watercolors bleed when being used.
I can definitely see this helping out in water colour emulation, and I don't think it would be to hard to create (however I'm not a dev so level of difficulty is debatable)
Furthermore it could be something that is a part of the brush parameters when creating various custom Krita brushes.
Thoughts?