I propose that Public Mobile offer the ability to create a plan that consists of 'Add-ons' only, doing away with restrictions like requiring a talk plan in order to add international/US minutes.
For instance, there are those who do not need unlimited talk or unlimited text but require only basic amounts.
An Add-on Only plan might consist of selecting the base plan (10/30/90 days) and paying a fee for that, then adding the talk (like 400 international/US long distance minutes, which can be used Canada-wide as well), adding a text add-on (which currently doesn't exist, but for sake of argument let's use $10 for 1000 texts world-wide), and adding a data add-on like 1 GB for $30.
This way, those who wish to have a very basic plan can do so while allowing some talk/text/ and data which rolls over and never expires.
As a further example, let's say this was possible with current pricing, I would select the 90 day plan and use add-ons for talk/text/ and data. My total plan costs would look something like this:
$25 - 90 Day Base Plan fee
$15 - Add-on 400 minutes International/US (and can be used for Canada-wide calling) that rolls over