Cool! I think the gradient background as a ground to lift the figures is interesting, as although the figures look flat, the contrast makes them look more distinct. I'd suggest to vary the quality of line, and by that I mean making the line thinner in places than others. You might make the line thicker where there is more body mass, or perhaps thinner where light hits a plane or surface. This brings me to the form of the figure. There isn't really a sense of three-dimensionality as the forms appear flat with no sense of contour (except for maybe the unicorn's horn). If you can imagine that the forms you are drawing are three dimensional, and visualize them in you mind's eye; you would be drawing forms rather than symbols. As they are shown here, the forms are rather flat and side on, almost like Ancient Egyptian hieroglyphics. What really get's me is the shape of the pony's hair/ mane with the light lavender streak at the horn between the two other bangs of the darker plum colour. Everything looks fairly organic, and that sharp geometric rendering of the hair is a little jarring. Perhaps try to follow the contour of the hair, and imagine gravity affecting it. Of course, geometric forms should be applied, but here I think it looks a little strange. If you're interested in playing with flat forms versus illusiory and apparent three-dimensional forms and geometry, look up some works by Picasso and Braque on analytical and synthetic cubism. There's nothing wrong with a flat, graphic aesthetic, but in my opinion a static pose like this could be enhanced with a cool rendering style or interesting composition to compensate. The composition is centered and smack-bang in the middle, and the application of colour is excuted in segments of homogenous, unmodulated segments. This reminds me of stain glass windows from Gothic architecture, Japanese Ukyo-e prints and Paul Gauguin and Emilé Bernard at the Pont-Aven school with their cloissonisme. If you're interested in making art in this fashion, I highly suggest looking up Gauguin, Bernard (others from the Pont-Aven school wouldn't hurt), Gothic architecture (particularly stain glass windows) and prints from Ando Hiroshige. I really do like the gaze and interaction of the two figures as their smiles can be interpreted differently (at least for me). It could be that they are simply two friends back-to-back posing for a double portrait; but the smiles could also be interpreted as confidence or competitiveness. Almost like they're back-to-back just before making ten paces to turn and draw like in a wild west shoot out. Interesting work. I'm looking forward to more and I hope my critique was useful to you.