So for your dining room, ideas to bring color in (not necessarily all at once):

1) Frame a grouping of your pictures from Colorado. Should take up a large space on the wall --

2) Gauze slipcovers for your chairs. Can still see the shape of the chairs but bring some light or color to the shape.

3) A really over the top rug

2) Reupholster the chairs. Add an upholstered bench in a coordinating fabric, you could keep it against the wall and switch it out with your chairs from time to time. here are some fabrics to give you ideas. These are at Hancock Fabrics, which I can be found almost anywhere: