All your cards are great... and fine as they are!!!
If you are interested in kicking them up a knotch:
: Wonderful image and the bling is awesome! You just need a piece of ribbon that coordinates to run behind your main image panel and tie on the left side. Perhaps a rich brown satin. Then three brads in the bottom right corner with your burgundy or green would be perfection.
I agree with the above poster who said there was a bit too much white. I would crop your image closer with an oval nestie or even just trim to a rectange, layer that on black layer with just an 1.8" showing. Then put that layer on top of the white top note die cut. BTW, I would always recommend matching your coloring to your paper... regardless of reality. (So, a pink wagon is needed here, the same pink that's in your paper.) Great bling on your flowers!
Super sweet! You just need some contrasting ribbon
to bring out the colors of your image, so maybe some pretty blue ribbon (the same color as your candles), I'd bring it up behind your green image panel from top to bottom, and tie the bow at the top of your image so the ribbon sits right on top of your adorable bday cake right where the pinkish one is now
Beautiful paper! I would color the tie image in the same colors as the beautiful Basic Grey paper. Then center the sentiment, "tie one on" rather than having it on top. I'd also put the Happy Birthday on the inside.
These are wonderful! Keep stamping!