Excellent dress designs, too. And Lyra's got shoes! She's really dressed herself in her very finest, hasn't she? And just for her special somepony on this special occasion, too. It's no wonder they love each other.
Wow, that's all smashing! The foreground ponies with their transparent clothes (those really look great!), very nice poses and expressions. Good work on their hair too - while Lyra and Bon Bon have very unique and good-looking manes and stand out that way, all the other ponies however are less attractive. I like other ponies in this drawing, some of them interacting with each other and telling us small stories (like the pony on the left, treading the flowers). The background is wonderful, with a lot of detail and just looking great!
Huh, it's so difficult to stop looking at it, as it's a piece of an amazing work. The effort you made to draw it is well visible.