Other than that, roving inspections would be all that is needed.
You are proposing this for VIA? Firstly, whatever system VIA uses for booking and fare management would have to be compatible across their system, or they would have to have different systems depending of the need and facilities of their various routes. What works in Kingston won't likely work in Gillam.
Do you (and others) propose to hire fare inspectors or load this onto the existing and, form what I have heard, limited on-board staff? On-board fare inspectors on GO aren't part of the operating crew, and can cover multiple trains in one shift. I'm not sure how that could be managed even in corridor service.
Even if VIA wanted to do such a thing, it would need legislation. GO offences are enabled by the Metrolinx Act, and enforcement personnel are designated as Provincial Offences Officers. I haven't researched it, but it seems any fare offences in VIA would have to be created under the Railways Safety Act. Enforcement personnel would have to be somehow empowered to enforce the Act. Currently, I believe the only people who can do that are police constables appointed under the Act ('Railway Police'). There is no authority for VIA to appoint enforcement personnel since VIA has no enabling legislation. Once you create a public-facing enforcement service, you create the need for specific HR, training, court liaison (across many jurisdictions), supervision, and on and on.
All quite do-able of course, provided Parliament is up for it, but outside of VIA's wheelhouse.