Getting to Canada -- securing my work permit, opening a bank account, finding an apartment -- turned out to be just the start of the things I needed to do in order to settle in here. Besides learning the ins and outs of my new apartment building and trying to find -- emphasis on find, supply chain problems are everywhere -- furniture so I didn't have to sleep on the floor, there were a few more bureaucratic hurdles I needed to jump through.
I've picked out the biggest three below, in the hopes that someone else might be able to plan for them better than I did.
Change your health care
I talked about this one before, in that you should not expect to have health care coverage when you first arrive. That said, one of the very first things you should do on arrival (you can't do it before you're here and have secured a Social Insurance Number) is sign up for health care in your province.
I say province, because Canadian health care is administered differently by each province. There's no one-stop federal service to sign up with, and they don't auto-enroll you when you get a SIN. Depending on the province, you'll be able to sign up online; the website for BC is here.
Note that there's normally a wait period before your covered, which could be 60-90 days. Which is why you should sign up as soon as you possibly can. This is the first thing I signed up for when I got here, and it was the last card to arrive.
Change your driver's license
Even if you don't plan to drive in your province (like me), if you have a driver's license, you should swap it out. For one thing, Canadians use their driver's licenses a lot as their primary means of ID, so getting one means you can stop carrying around your passport everywhere. In addition, it's often illegal for you to keep your old out-of-Canada license past a certain point (in BC it's 90 days), so the sooner you take care of it, the better.
Unlike the California DMV, I found going to ICBC to actually be delightful. I made an appointment online, got seen immediately, got my eyes tested (they're stricter here, and won't let me drive without my glasses, which made me feel oddly safer), and took an oral "test" where they asked me what I'd do in certain situations, and then corrected my answers as I gave them. That is, instead of the test being a way to filter me out, it became a way of bringing me in, of letting me know some of the key differences in driving in BC versus the US.
The picture was still terrible. I think that's just a law of the universe, though.
Change your phone number
This one seems trivial, but don't ignore it. Not only did I rapidly get tired of having to give my country code out everywhere, my cell service was terrible for any local call, and I hit my roaming data cap really fast.
Your cell number affects your credit, as well. Remember how you won't have a credit history when you move here? Well, without a local phone number, you can't even apply for some of the credit cards you could use to build that credit history. You'll be stuck going to your bank, hat in hand, begging them to take pity on you and "give" you a credit card.
Since I plan on going back and forth to the States for the next year or so, I got a separate phone for my Canadian number, and I'm thankful I did. Calls don't sound like staticky garbage anymore, and I have a local, properly Victorian number I can hand out. I even went the extra step of setting up a localized (Canadian) Apple Id for the phone, which has also helped clear up some issues I'd been having with using my debit card (but that's a whole other post).
Conclusion
So: phone number, driver's license, local health services plan. Get 'em switched over as soon as you can after moving, so you can actually start to relax, explore, and enjoy your new home.