The painting style right now feels a little "distant." Almost like we're looking at them through a very long zoom lens and some fog. I think that can be solved by getting a bit more contrast in there, instead of using values all very similar to one another. If you convert them to grayscale images it will probably be more apparent.
Of course, I'm not a huge painting-guy so that may be way off base! I'll let someone else agree or disagree who really knows their stuff.