I am aware that I should stick to flying below the freezing level, avoid precipitation, increase landing and T/O distances, de-ice the A/C before flight, check for carb icing....I have also read the CAA's guide to winter flying.
No, yes, no, yes and yes, respectively.
Flying above the freezing level is perfectly fine as long as there is no visible moisture (clouds) in the air. DO NOT fly through cloud, not even just a little bit, unless you have a fully de-iced aircraft.
Precipitation is no problem when well below the freezing level (so ambient temp well above freezing) but might be a problem close to, or above the freezing level. See above. Biggest problem is that precip in general, and snow in particular, reduces visibility, so VFR pilots tend to avoid it even in summer.
T/O distances are generally shorter. Cold air is denser so more air getting into the cylinders and more air for the prop to bite. Also your TAS is slightly lower in cold air than in warm air for the same IAS, so shorter landing distances as well. Check the POH! Of course, as soon as the runway is wet or snowed/slushed/iced over, all bets are off.
Yes, the airframe needs to be deiced before take-off. Obviously. Bloody hard work too. Unless you have a heated hangar you can use for a few minutes. Do make sure that all the melted ice is swept away from hinges etc otherwise it will re-freeze there quickly, potentially jamming your controls.
Carb ice should be checked for as per normal procedure but the worst cases of carb ice actually happen at about +15C and 100% humidity - check the CAA charts. With temperatures at approximately -15C applying carb ice can actually be dangerous: without carb heat the ice crystals in the air pass through the carburetor without any influence, but if you heat them up by applying carb heat, they melt and may subsequently cause carb ice because of the venturi/evaporation.
Checking for water in your fuel is also much harder when the aircraft is cold-soaked after a freezing night. Be careful with scraping ice off your windows: they are generally much more susceptible to scratches than your car windshield.