Thanks @walperion and please forgive the lateness of my reply. When I block in a painting I am not interested in detail, I just want to get in the basic forms and colours and set the overall tonality of the painting.

After the blocking-in process is complete I build up the layers and refine the detail. Whilst I like detailed paintings I try not to go overboard as I feel that too much detail often kills the vibrancy and life of the painting. Often the suggestion of detail is more than enough as the human brain fills in the rest of the details.

I have been using liquin to thin the paint and it also speeds up the drying. Quality of brushes will help with the blurriness issue. I'd recommend adding Rosemary and Co, Ivory Dagger brushes to your collection, you can achieve some beautiful brush strokes with them.