If you want some extra flavors, add them after fermentation is complete and the yeast have stopped eating and altering.
I have been making hard cider for a couple years now, and started experimenting with spiced cider for fall/winter that first year. What I've done is to add a small muslin bag of whole mulling spices and dried sweet orange peel into the secondary. At first, I was leaving my cider in primary for about a month, racking into the secondary where it remained with the spices for another month, and then bottling. The results were pretty good. The spices came out in the finished product pretty nicely, if a little weak. So what I'm experimenting with now is crushing up the whole spices more, the amount of spices used, and shortening the overall fermenting time.
My base recipe is either cider or juice, and (for the holiday cider) 1/2 cup per gallon brown sugar for the slight molasses influence. A pinch of high alcohol yeast nutrient and yeast. For yeast, I'm still playing around with different ones. Those I've used most were: Wyeast sweet mead, Wyeast cider, Safale 5, Lalvin 17b 1122. The Lalvin had been recommended to me as bringing out more of the apple flavor, but I like the speed that the Safale gets the job done with (being a somewhat impatient person). I haven't noticed strong taste differences in these. But admittedly, I haven't been doing side by side comparisons. They all taste pretty good to me. O.g. is usually in the 1.060 range, and the finished product is usually just over 8% ABV and bottle conditioned to around 2.5 volumes.
I have noticed that if the cider sits for a year or two, the spice flavor diminishes. So it's been best in that first year.
I by no means consider myself an expert. This is just what I've been playing around with now and then over the last few years. I hope someone finds my experience helpful and can add to it. Like everyone else, I'm always looking to improve my results.