What other vegetables can I roast with asparagus? I eat roasted vegetables at least once a week.

I usually combine two or three veggies (broccoli with cauliflower, potatoes with carrots and onions, Brussels sprouts with carrots and parsnips, etc.), toss with olive oil, salt and pepper, maybe some garlic and onion powder or herbs, and roast at 225°C / 450°F for about half an hour.

I would love to add asparagus into the rotation. The problem is that it cooks so much faster than the other veggies I'm used to working with (often just 10-12 minutes at the same temperature).

Is there another vegetable that I can roast with asparagus (aside from "white asparagus"!) that will cook as quickly, or am I stuck with two different roasting times?

Spring vegetables that are available fresh in southern Ontario, Canada would be ideal.
Vegetable roasting times are somewhat depending on what kind of vegetable it is--broccoli is always going to take longer than spring peas.  But mostly, it is dependent on the size to which you cut them.

So cutting your other vegetables in smaller pieces will help.

Also, you can start, for example, carrots and broccoli, and give them a ten minute head start, then add the asparagus.