I have to go back to Canada to settle some business, and I was thinking about rescheduling the return portion of my ticket, scheduled to go back in April, and then returning to Thailand with a one way ticket. If I have a valid work permit and a place to live, is there any trouble coming into Thailand with a one way ticket? Will I get any hassle?

if you have a WP then you have also a visa so it is no problem to enter thailand with a one way ticket

If you have a Visa there will be no problem.

Your will require a valid visa or if on an extension of stay (would require a re-entry permit and return before the extension of stay expires).