At first I didn't like the spoiler on my '12 coupe. I was gonna buy an ex trunk just to swap, but the spoiler has grown on me... Now I actually like it. It gives a great direction to the rear line when viewed directly from a perpendicular angle.
But I agree with a previous poster, I like the duck bill style on the new accords. I'd be interested to see someone do a custom si coupe duckbill to replace the current spoiler.
If you want a bigger spoiler I've seen an 8thgen mugen wing on a coupe and it doesn't look horrible. Not my cup of tea, but hey lol.