My first choice would be a floor heating pad with an air temp thermostat.  Put it on a daily timer and turn it off when not needed.  A decent heated towel rail on a timer will help too.

Second: A slimline wall panel heater on a timer.  We just put a top vented Dimplex model in our bedroom, it does fantastic job heating a 25m2 bedroom quite quickly and has a built in timer.

Third: A little fan heater, mounted high and pointing down.  I wouldn't put one of them on a timer.  They heat up a room in a few minutes to an acceptable temperature. 

Heat-lamps don't do much IME.