I found a review on the other place about water soluble oil paints and apparently the brand they tried was quite thick which would work nicely for me. However the upshot was that cleaning with soap and water alone was possible, it was very slow and inefficient so the person ended up using mineral spirits to clean the brushes. Which I could do outside afterwards in a disposable container and then let it evaporate outside to dispose of the solids in the bin or through the council. However I don’t have that many brushes so might need to clean my brushes between colours, and it’s not practical for me to be outside the whole time. Also the mixture doesn’t maintain integrity and stability when thinned with water, so I would still be dealing with linseed oil and the flammability involved. I’ve been trying out a technique using coloured pencils instead… The idea and some of the effect is the same but let’s say while the medium is much safer and more convenient (especially working from bed) it leaves a lot to be desired. Despite careful sharpening and patient light handed layering there’s still patchiness and weak colour payoff. ___