Depending on how much you have to cancel trips, it may still be cheaper to have non-refundable tickets.

If you take ten $1,500 fully refundable trips and cancel one, you've spent $13,500. If you take ten $500 non-refundable trips and cancel one, that's $5,000. So you're spending $8,500 to save $1,500.

My company has taken to buying mostly restricted tickets, and has saved a lot doing this.