I like my cider "naked" for the most part, but some light toast American oak will be nice. Just don't overdo! A small amount in one gallon would be all that's needed- say, maybe, 1/3 of an ounce for a week. Then taste and see if it's too much, or just enough. You want it to be a little more than just enough, if that makes sense. It will age over a month or two nicely.
As far as other additions, I don't have much experience with that.
Broken Leg Brewery
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