If you are starting in Sudbury Wild is probably what you will face. Along the Saint Lawrence and the lakes, it would be a combo of things, I guess, I did that route a few times, the lakes one. I'm only picking you up on the point because that may be helpful in your situation with other boards, or whatever. Myself, I find the fragmentation of camping styles and all the arguments around them a little annoying, though I pitch in.

I suppose one other thing is that ideally when stealth camping, one should always pretend one is wild camping. So if I pick a wild looking scrap, I would be all innocence that I was trespassing if ever challenged. Of course the whole point of stealth camping is that they will never know you were there. By the way, it isn't lying, it is normally pretty much impossible to know who owns what, or what rules cover it on a long bike tour. So I just subscribe to my side of the argument.

The biggest problem with stealth camping is that the behaviour required interferes with the camping process. Like you cycle till you can barely see the surroundings then you get into your camp, no shower, campfire, cooking, etc... Then you wake up at dawn, no washing no rest room, and you take off again. You are not going to be discovered, even in enemy territory, ask the SAS, but you just don't have the kind of dream situation you have when wild camping, etc...

In ontario, one of the better forms of cycle touring is on roads in the bush, or snowmobile trails. Definitely the best tours I have had here was on those kinds of roads. You can wild camp or fish wherever you want. You see lots of animals, often at close range. If you google ontario trails, you will find a comprehensive list, and discover most of them are snowmobile trails, some nearly 900 km long, or longer. Unfortunately they are often impassable, generally, or in places, so you have to do your homework.