You'll get there far too soon
As you get better at estimating your coasting distance, your fuel use will drop.
Don't stay in 1st or 2nd gear in a traffic jam - it uses too much fuel.
Try to avoid 1st at all, unless for starting from a stop, and use 2nd and coasting.
Once the engine is thoroughly warm, you can use some really high gear when the engine doesn't have to work hard.
I'm doing 30km/h in 4th , 45-50 in 5th with a 1L engine .
Works well as long as it's flat, shouldn't be much of a problem in the Netherlands. I Don't accelerate in these gears though - the li'l car will pull it off, but I can hear and feel it doesn't like it much.
In city driving, my fuel consumption drops or stays the same now - before joining ecomodder, it always skyrocketed during city driving.
Pulsing briefly and then coasting is extremely effective in city driving.