I want to preface that I think your work is great, and that you ARE on the right track. Everyone has given you great advice... this is just one thing I caught in the portraits, because I have used the same style. Which is to use a layer of grunge for the background...
What I think you did here is apply the grunge AFTER the piece was done, which I hope can still be altered. I think when this is done after the fact, the tendency is to make the piece look muddy. I have marked with red arrows where your whites are disappearing from their brightness. And where your colors are looking more speckly and not adding anything to the piece as a whole.
Also watch out for applying this effect too dark or opaque. It tends to take away from the surrounding areas.
Like the side of man's nose and chin, the girl's braid, and parts of the man's coat. This can be avoided if the grunge layer is on it's own layer, so that it can be adjusted. I would turn the opacity down slightly so that the man's face comes forward more. And erase it out of the braid, the coat, the collar, her eyes, and his white shirt...
I know you meant to do this, but the grunge is overpowering all the other great stuff you did, so much so that I saw it first. Cause it covered up all your great little details, and you don't want that to happen. This is just my opinion. I hope I haven't offended you... I see in your new piece you didn't use grunge at all, and it's full of bright wonderful color.
But I do get why you did use it for the single pieces, it gives a nice " antique-y " feel to them, like old photographs.
