For me, the high beams on my '95 and '96 Dodge Ram trucks are inadequate. Certainly, this likely has something to do with my being 73. I avoid driving in the dark, but sometimes I must. I keep both the inside and the outside of my windshield clean, and the pitting from sand, etc is minimal.
Because of lens polish, my headlights are as clear as I can make them. I also keep my spectacles clean. Still, I have been looking for ways to shine light further down the highway. Recently, a salesman at an auto parts store was promoting a $400 12" light bar with switchable flood and spot LEDs. Very powerful.
Could I legally use this on BC highways at night? (Assuming I were to mount this light bar at the legal height, at the centre of the bumper, and have them properly aimed.)
Could I legally have a switch that enabled/disabled the hi/lo beam in conjuction with my OEM hi/lo switch in the cab? (I am aware that certain after-market lights must be disabled when the hi beam is on - but I'll need these lights during hi beam operation.)
There is a nice resource for the inspectors in designated inspection facilities to help them (and now you) to determine the legality of lights installed on a vehicle.
Beware of the lights that you are being sold. As soon as I read flood and spot instead of fog and driving I became concerned. Flood and spot would qualify as off road lamps and would have to be covered when you are driving on the highway. (Highway = any place where you must have license and insurance to drive)
It's great that you recognize the need to keep your headlight lenses clean and clear. Judging by what I see when I walk past parked vehicles these days I realize that many people are happy that the lights light up and don't realize that a yellowed, foggy lens needs some TLC from a cleaning kit. I'm sure that you do it as a matter of course, but since you didn't mention it, I might add the importance of keeping your windshield clean, both inside and out for better night vision.
Provincial rules regarding lights/lamps can be found under the Motor Vehicle Act Regulations Division 4 (click on hyperlink please). There are almost certainly federal regulations to consider as well; for instance, Daytime Running Lights have been mandatory in Canada for about 23 years now; many of these operate by illuminating the high-beams at low voltage. Federal regulations may be found in the Motor Vehicle Safety Act.
Legal height is under MVA(R) 4.05(2).
Minimum range/reach of highbeams is under MVA(R) 4.06(1)(a). There doesn't appear to be a maxium range or brilliance.
Somewhere in the depths of memory, I'm sure there's a rule dictating that no more than four beams may simultaneously be on, but darned if I can find it right now! For Ram Pickups from around 1994-2001 it would appear from pictures found on the interweb that this would only be relevant if your vehicle also had driving lights set into the front bumper that could be lit at the same time as the main beams (which are evidently low/high beam units, so considered one lamp on each side).
Of particular relevance to your last question, see MVA(R) 4.09(3). I would interpret this as making it mandatory that those auxiliary lights you wish to install be wired only via the high beam switch (you would no doubt want to use a relay, as the draw on those beams will be pretty high).