I've gone a different direction with this. I don't think the top 10 of the year thing is feasible because it effectively eliminates all stories written in the latter few months, as they might not reach the requisite 100 ratings necessary to get a ranking.
We'd have to award the points for the year before last every january (i.e. storygames published in 2015 are awarded in jan 2017) but I think you'll find that those stories are recognized well enough in the next update.