Christien, as you did a commercial import you have to go thru the commercial side of customs. Commercial imports are for resale. When you import for personal use, the process is a lot simpler and faster. Stop at US customs first. Pull up to CDN customs window, tell them what you got, go in with the bills, they fill out the paperwork, pay them and your done. Every car that I have brought back has taken less than 15 min to clear customs.
The difference on just having the car shipped to a drop point in the USA and having it shipped here was $800 last time I had a quote. Add the $300 you mentioned and it starts to add up to a nice set of rims.
As to the traffic in and around Toronto....sorry it's to late to teach them how to drive