Multiple things to answer here...
DAP, saying they increase our vulnerability is a non-starter unless you are doctrinally stating that no soldiers should ever move dismounted anywhere from now on because we are too soft. All of the other requirements you listed are basically insignificant, as they are cheaper, more fuel efficient, lighter, easier to learn, etc etc than just about everything we have short of adopting bicycles.
Haggis, I know the CF has used them sparingly, which is where I have learned how useful they are. Because they were locally acquired for an op somewhere or because 3 RCR did a quasi trial with them does not mean that the CF has incorporated them organically like I am suggesting. My experience with them is building a massive live-fire range with them and we used them to haul sand bags and the heavy SITs all over the place. I was hooked from then on.
Techno and Rogo, I am not suggesting any sort of fighting vehicle, but a purely logistic-based vehicle. It is a pack mule for kit that can go almost anywhere (please nobody be a goof and post a photo of an ATV getting stuck or looking at a cliff, you know what I mean by mobility and almost anywhere). My suggestion is just to have ATVs with trailers or side-by-sides with a cargo area in the back that anything you want could go in.
So to wrap this up, if anyone is trying to imagine a combat vehicle like a german motorcycle with an MG42 on the sidecar you are making this far more complicated than it needs to be. It's a pack mule that you don't have to worry about walking off on you, that's all.