Since moving in to his own room, DS has had the same bedtime routine: 2 stories sitting on my lap in the chair, a cuddle, a drink, and then down into bed. Zipped into sleeping bag, a kiss goodnight, all lights off, door shut, I head into the kitchen and pour a glass of wine 
From about 5mo he has always self settled quite happily: babbling or sometimes grizzling for 5 mins or so before going to sleep. never crying in distress.
Now at 15mo he has started resisting it, grabbing at my hand, crying, doesn't want me to leave the room etc. I guess this is just a phase of separation anxiety, but I am wondering whether it's partly cos I am being a bit of a meanie and turning all the lights out and leaving him in the pitch dark?? he doesn't have any toys in his cot either. He does have his numnums (dummy!) clipped onto his sleeping bag and this is his only comfort object (never shown any interest in teddies or blankies etc - have offered them and been ignored in favour of fire engines and diggers!).
Is it time to introduce a nightlight? Or some toys in the cot?? TBH i have always resisted this idea (he never even had a cot mobile as a tiny baby!) cos he is a very hyper, full-on, 'spirited' little boy who barely naps during the day and never has ANY down time. he wont even watch telly. he just runs around all day. And previously the only way to get him to sleep was to put him into complete darkness....!
Wondering what other people do with their toddlers?? I can only imagine that if I start introducing toys and a light he will just rawl around in his cot for hours refusing to go to sleep??