There are safer alternatives.
In the United States there's been a lot of concern about voters in the military overseas, because it takes a long time, and about people with disabilities. What's done there, and I think this could be done in Canada, is that you can make the blank ballot available online. In the U.S. for military voters, by law it's made available at least 45 days in advance of the election. They download the ballot, print it out, fill it out, and mail it in.
Now, with voters with disabilities, you could download the ballot onto the computer, and they could use their tools to vote. One thing you need to be careful about is that when that happens, you don't want their computer communicating with the main server, because that's basically Internet voting again, and you have lots of issues, such as the secret ballot. But they can download it onto their computer, disconnect from the Internet, and then fill it out locally so that they can take advantage of the tools they have. A blind voter can fill it out, print it out, and then mail it in by postal mail. Again, they can use the tools, and if it's done enough in advance, they don't have to worry about the time for the postal mail.