Well from just an image its pretty hard to tell how it looks in motion, but the two things that stand out are the blocks (which I assume move down) and the UI.
The blocks look pretty bland, and since I imagine thats where a lot of the player's focus will be, making them more interesting will help a lot, maybe try none rectangular shapes or leaving a trail, or maybe have them change colour as they fall, with brighter colours closer to the receptacles.
For the UI I'd remove the list of "text: number" things, instead try larger visual descriptions, like I see you have a score and a target score, why not make it a bar of some kind? If that is vital information you should also make it big and very easily readable, so that if during an intense sequence when the player has only a fraction of a second they can still glance up and immediately know how far they've gone, or even be readable with peripheral vision. Other UI elements like the streak counter could stay about the same, except maybe moving it into its own corner, you could also have the "Streak" part small (the player only needs to read it once ever) and then make the number massive and colourful block text, so again it can be read from a glance, as well as be more visually appealing. I don't know what the other two white numbers mean so I don't have any suggestions but I think you get what I'm saying, your graphical overlay should be easier to read, and more exciting.
The only other thing I can think of is animating the wire frame thing in the background, but since I've only seen an image, I don't know if it isn't animated already. For more information on juice this video is pretty useful:
Developer
