Battery?
 

I know I can improve my travel fuel economy if I start engine off coasting - and turning off at lights and the like.

In my new car though I'm not keen on causing problems with clutch starting or running down the new battery via starting at lights.

There is just one set of lights on my usual trip to work, the total trip takes around 15 minutes - how can I be sure that the battery won't be worn down in a hurry doing that?

Then I'd have to consider engine off coasting using clutch to start - this would mean the alternator would then not be charging the battery (I'm not doing any of this yet in the new car - but thinking about it..)

If you are really worried about the battery then get a battery charger and every month or so top off the battery, it's good for the battery to get fully charged every once in a while even with normal driving.
But to the root of your question, I don't think restarting in the middle of a 15 minute trip is going to shorten your battery life much, think of all of the delivery drivers who restart their cars every 3 minutes or the people who only drive 5 minute trips, my trip to work is about 10 minutes and I shut my engine off mid way and my battery is nearing 5 years old, twice a year I top it off with a charger just to make sure it's full and healthy and I don't have any issues with it starting on the coldest winter mornings.

depends on your particular drive. If your commute is during the day and you drive with lights/heater fan/radio off. restarting once is really not going to make much of a difference. If you drive both ways (or one way) in the cold and dark with lights on and/or the heater on high, and always have the radio blasting (Like me), The amount of time your battery will go between charges will be greatly deminished. The question is mostly will your car make it to work and back on a single charge, a 15 minute commute? I'm thinking it wont be an issue. recharging a battery is NOT a bad thing. and, in fact, you battery will probably last longer with occasional full charges than it would with a constant trickle.

Reasonable questions, but not the big issues you're worried they might be. The alternator will produce enough power when the engine is on to re-juice the battery in normal daytime driving. Pay attention to electrical load by turning off stuff you don't need: if you are running the radio at the stop light, then use the parking break to at least cut the brakelights. Cut the radio when you go to start. If I read my meter right, cutting these things makes more power available to the starter when you restart. Buy a charger: you'll get some or all of your money back in extended battery life.:thumbup:

But most importantly, enjoy the car and don't worry. It was well-engineered and will do what you need.:thumbup:

EDIT: just checked your Pulsar's page. Are you sure that curb weight is correct? 1200lbs is lighter than a VW bug, and half the weight of most civics circa 2000. Regardless, EOC and P&G are pathways to much more in MPG from this car. You've left a lot on the table.