Unless you wanted to install lesser lamps, but more of them I don't see if you could make an improvement to the current setup. Despite having visited your house I cannot remember seeing a bollard.
I'd think 3 or 4 GU10 style down lighters in the soffit of your garage and a lantern outside your front door with a smaller lamp in you bollard would save you a little bit of energy, but is it worth all the hassle?
Assuming you pay ~15p/KWh for your magic invisible energy.
Using this website...
http://projectbritain.com/weather/sunshine.htm
I have worked out we AVERAGE 11.7 hours of dark each night.
11.7 hours multiplied by 365 days of the year comes back at 4270.5 hours the light is on every year.
Your current 70w lamp on for 4270.5 hours will consume 298.94KWh and cost £44.76 to run.
Lets reaplce 70w SON-E for an LED lamp. I'm going to pick a Phillips 8.5w E27 LED lamp that produces 806lm.
I'm going to install 2N° Phillips Robin MyGarden hanging lantern outside your front door. They're 4.5w and produce 430lm. I've recently fitted a few of these and they're fantastic luminaires.
I'm also going to install 3N°IP65 GU10 luminaires into the soffit of your garage with 3N° Phillips 4.6w GU10 lamps that produce 390lm each.
The above setup will consume...
(8.5+(2*4.5)+(3*4.6) = 31.3 watts total.
(31.3*4270.5)/1000 =
133.67KWh a year
133.67*0.15 =
£20.05 a year to run.
https://www.screwfix.com/p/philips-es-g ... 8-5w/7715p
https://www.toolstation.com/philips-led ... p44/p45290
https://www.screwfix.com/p/philips-gu10 ... pack/3995p