I thought about best movie, but given the osu! community, we would have to vote on movies that came out last year (since they take 9 months or so to come out on DVD/BD) and there would be like 4-5 movies to vote on, which is really small. On top of that, I don't even know how many people have actually watched an anime movie that came out this year. I have a feeling that number is also small.
If you can show 2 other people thinking it will be worthwhile to vote for, I'll add it, but I think it is slightly silly (movies are already allowed for all anime categories already).