My recommendation for the time being, don't be afraid to throw in some darker darks and lighter lights. Nothing wrong with contrast. In the event that it seems up your alley, I've always thought that whatever we're posting, good, bad, full of wonderous brushstrokes or fumbling along the learning curve - we should always feel the freedom to present the pieces proudly and strongly.
Might try working on a piece, working with the contrast in the aftermath of said piece, and then using the final presentation as a pallette for future works. There's a whole bunch of colors and tints out there, don't be afraid to use them regardless of consequence.