Well at least I decided that I should now stop working on it. Since taking a week's break from it I took time to look at it closely and try to see what was missing. What I did was try to define the colors a bit better - so now the dog, the cat and the saint's clothing have taken on different hues. The minimalist background landscape also had its hues and shadows tuned up a tad. Perhaps more important, the columns have been given a greenish tinge and this color was also added to the triangular spaces in which the angels float. This has helped to give some "weight" to the architectural elements around the main image.
I am still in some doubt about this work...to me it seems like it sits slightly uncomfortably between several stools....
I prefer to think of it as a reasonably decent specimen of naive art at best.
I will probably try my hand at something a bit simpler next.