Just from what you've written here, you've shown that you have a basic of understanding of your renovation design goals: to do what you can to open up living spaces, and to choose materials that pull together your chosen color palette. 

I generally put them on color coded key rings to organize everything. 

I would also agree that everyone brings their own lens to the world (and economics) which colors their behavior and advice.  

New flooring, lighting, paint (light gray is a nice color), is that a full wall in the back of the picture?

I use Shaw Kitteredge (color Fog)...see below.  

Add a garden bed with mulch and some colored flowers.

(i.e paint the cabinets white get new stainless steal knobs,  paint the walsl _____ color, white trim?

What is a good size for the post card and should it be in color?

I don't care how good that color looks on her, how stylish her dress is or how much you love her hair.  

The more colors you use the more you have to keep track of.