If I have a large surface area, then sometimes I may use my AB and spray with Iso. Another point I will mention, is that every time I go to work on a kit I always wash my hands first to remove grease from them.
For years I never cleaned the sprues & component parts, but that was when almost all my paints were Humbrol enamels, and they stuck & covered very well
As a returnee I still use enamels, many of them years old, but some of the other brands I have purchased recently are thinner, as are the current Humbrol enamels, and I have also acquired a few acrylics. Although I haven't experienced any pooling or non - adherence, some of them don't seem to cover very well, so I have started washing my sprues
I have two shallow plastic trays, one containing water + a few drops of washing up liquid; and one plain water. Fairly obviously I wash in the soapy water first then rinse; sort of swish it about and also use a soft brush, actually a make-up brush begged from my daughter
If there has been a lot of filling & sanding I carefully wash/brush in a similar manner
Then I spread them out on kitchen towel or a soft tea towel to dry overnight
I suppose I could use a mixture of meths & water for the rinse, and keep it in a jar for the next time
I never clean the spruce, that's part of being a model maker it proves your doing it right plus, if you drop the part you have painted it's easier to pick it up again without touching the part you have painted:D
No, I don't wash my sprues and only once have I needed do and that was an old Italeri SR-71 Blackbird kit.
Modern kits doesn't seem to have mould release on them for some reason? Perhaps they're using a different polymer mixture? I don't know.
Also using Tamiya paint with 50% iso and no primer this isn't an issue anyway since Tamiya paint sticks to everything! ;)