Only compensation you're entitled to is full refund of your ticket.
They just changed that YVR-MIA flight to a red eye; it's one long nasty flight on an A319 especially when it's overnight.
Here's what I suggest you do:
Call AC back and tell them the late departure is not acceptable. Ask them to route you through YYZ. You can take the 6:30am to YYZ and that will connect you to the 3:50pm to MIA. (2 hours connection time)