Regarding using different color polish, I have some light tan shoes that I was unable to really fix the scuff marks on so I used darker brown polish on the toe. It looks pretty good to me.
I have some full brogue brown shoes that I often wear with a kilt but my sporran (chosen by my wife)is black. I am considering applying some black polish to the toes and heels, sort of a subtle spectator I would probably us the Safir cream polish as it is touted to have more pigment.

I do like your brown jump boots and had a pair once. I do not think that the flex part of the shoe looks good with a mirror shine. And preferred your first effort.