Your artificial picture is the first example is a valid "colour pop" I've seen... Nicely done - the partial b&w works - as you say, it is pretty much monochrome already, and the intense colours in the creeper works very nicely against the background.
I rather like your autumn picture as well. A lovely back story, and the composition a lighting works together nicely for a beautifully warm and seasonal image.
Lovely humour in your rather charismatic and damp cat. I can feel the suspicion from here!