With the growing amount of customers purchasing phones outright a SIM only plan should be implemented beyond the benefit of a 10% discount. The customer costs 0 dollars with 0 risk associated since they remain purely profitable. The Koodo kiosks already have unlocking tools available in store.
The real corner of the market that this targets is the prepaid customers who want cheap plans or specific needs. Say customers who use no minutes but lots of texting and data. No company offers options that are really flexible to a customer's changing needs because of the need to pay off the device on the plan.
A SIM only plan could consist of a 10 dollar monthly fee with texting included (this adds incentives for prepaid customers to switch to monthly billing which does generate more money long term)
Then you could add minutes features ranging from 100 a month to unlimited minutes and then optional data features reminiscent of the data lightweight and heavyweight.
$10 - 100 minutes
$20 - 500 minutes
$30 - Unlimited
$10 - 500MB
$20 - 1GB
$30 - 3GB+ (each additional GB is $10 capping out at 5)
I think this would really shake up the market and bring a lot of new business in.