A couple of rules I'm trying to follow are extensions of
Be gentle on the loud pedal, look far ahead, anticipate, start coasting as soon as you know you'll probably have to decelerate or come to a stop soon.
If you're starting off in traffic and you don't think you'll get to the traffic light before it goes red : be gentle and try to keep it in the Motor Only zone;
No point letting the engine turn on if it's just a tiny sprint before the next lights.
When you're thinking brakes will be needed, try to avoid hitting the bottom of the charge zone - that's when you've reached the maximum rate of energy regeneration and braking heavier leads to using brake pads. It means starting the braking earlier and being more gentle.
Temperature affects the braking thing - when the batteries aren't in the correct temperature zone the maximum recharge and discharge rates aren't as high as they can be, so mechanical braking takes over from electro-braking earlier.
Cold running - I'm thinking working the car a little harder may help when just starting out when it's cold. Idea is that it'll warm up the bits quicker.
Motorway speeds - I need to do more motorway driving to figure this out more but economy will be better if the car can settle to low rpm. In sport mode, I managed to keep consistent 75mph with the car settling to about 2250rpm. In normal, I was having trouble keeping to the consistent 75mph. I think if you keep a consistent speed, the car will allow the revs to drop as the gearing goes higher. Constantly changing speed leads to the gearing staying lower. Kinda like the car going for 8th gear instead of staying in 5th.
Sport vs Normal - I'm likely to do my first real extended motorway run this weekend, so I'll know more about whether Sport works better than Normal when going at motorway speeds.
Stop-start - if you know you're in for a little while of 0-15mph stop-start traffic, use Eco. It lessens throttle response for a more chilled out trundle. Nothing to do with economy

Just that sport ain't what you want if you're only going to go 50 yards and then stop again
Last thought - hybrid is all about smoothing out the energy you use. You put energy in by letting the engine burn fuel, you don't want to waste that energy by letting it make the brakes get warm.