He's not expecting to land a flying job straight away, although it would be great. I think he expects to get a dock/ramp job first, then work his way into a flight job. The idea is to get some good flying experience, and be relatively well-prepared for finding work.
Ramp job is unlikely - a lot a students, not many jobs, he's only 16, and he can't drive a car yet due to graduated license requirements, and it's 50 kms to the airport. He could buy a Ninja 1400 that goes 330 km/hr, and the province is cool with that (he actually has a Ninja 250) but he's not allowed in a Kia for another six months

Again, maybe a year after high-school working any job, and flying at the same time, would not be a bad thing, but if he is able to land a dock job straight out of school and take the Challenger with him, he can build some general work experience and some hours/experience. However, if this forum is any indication, the hostility towards anyone with a bit of family money might make having his own plane when working a dock job a two-edged sword.
I will talk to him about building some life experience, but I'm letting him make his own decisions. If he winds up not able to get a job, he'll deal with it, and take whatever path he needs to. Haters to the contrary, this is his plan, not mine.
The RPP comes for free when he passes the PPL test - I confirmed that with Transport Canada this morning. No separate test required. I'll encourage him to gain some variety of flying experience - maybe a road trip as you suggest.