It's really amazing how color and scale can affect a card...especially a clean and simple card where there is no place to hide! If you make a card that doesn't seem quite right, ask yourself if a simple change in color or scale (or both, in this case!) might make a difference.
To fix it, I switched to Old Olive ink from StampinUp (which sadly doesn't stamp as crisply with the PTI stamps sometimes), and found some tiny rhinestones to mix in with the small ones.
stamps: Papertrey Way to Go, Kiddo; Birthday Basics
ink: Memento pear tart; SU close to cocoa, old olive
paper: PTI white
accessories: Rhinestones, scallop scissors to round the corners of the card