So, I'm just going to give my 2 cents on the whole fare integration scheme:
What exactly is Metrolinx trying to accomplish with the fare by distance? In general, eliminating cross-subsidies is a good thing if it is able to influence behaviour and consequently reduce costs. For example, airlines charging for luggage. By charging for luggage, they are able to charge less for the people who don't have luggage and maintain the same profit margins. But by adding a penalty for those who bring luggage, fliers respond to the economic disincentive by bringing less luggage, which reduces fuel consumption and the amount of baggage handling required, resulting in a cost reduction. Thus airlines are able to reduce the average cost of fares (because their costs are lesser).
With fare by distance, are we really incentivizing shorter trips? People take public transit to get from A to B, so unless people are being priced out of taking public transit altogether (switching to bikes or cars) the amount of vehicle kilometers should be fairly inelastic with respect to price. The only way that this would reduce vehicle kilometers is if people respond to the increased price by moving closer to their destinations, which is unlikely given the overhead involved.
Instead of costing with respect to distance traveled, transit agencies would be much better served by charging with respect to time of day. Peak hour demand is what determines fleet size and required capacity of the system, and concomitantly the maintenance and capital costs of the system. The marginal cost of adding off-peak demand is fractions of what it costs to add to peak demand, since there is no required increase in fleet/staffing. Wouldn't it then be more effective to incentivize the shifting of demand from peak to off peak? People are unlikely to change residence to save a small amount of money monthly, but if their hours are flexible they may be willing to wake up early/work late regularly to save money.
Adding the capability to track distance traveled is complicated and requires expensive capacity-reducing fare gates to stations that were never designed for them, and introduces demand for parallel bus service when people would be better served travelling on the higher capacity modes. Charging by time of day is easy to implement, and Presto is already capable of performing this.