it has a typical macrophylla shape for a young specimen to me. many container-grown plants will begin to look bad at this time of the year while still at the garden centers (lack of water, too much sun, too little sun, etc.).
these plants normally bloom at the terminal ends of the branches. you can cut them back and maybe get two flowering branches coming off the sides next year but i don't personally care for that look.
a location with morning sun will be fine and, once established, the plant should begin putting forth new growth.
if you give it a couple more seasons, new canes will come from the base of the shrub and fill in.

I'll leave it alone, then. I can do that if I try really hard, as I'm itching to prune it or fix it somehow. The other machrophyllas I purchased at the same nursery were all full and lush when I bought them. Just this poor girl was kind of pathetic. Thank you for your advice.