I kinda agree with Sailor Moon in that the amount should be around 150 songs but I think the filters should almost be illiminated. I have two songs on my list that I haven't heard for months because they match too much with hundreds of other songs that were played. Also the 200 songs kinda irk me when 200 songs is more than an 8 hour work day (on average). This combination meant that a lot of the more popular songs have to be heard only once or twice a day at most before it is banned from the listener base. Like I stated before, if there is a popular song for whatever reason and someone wants to hear it then it should be able to be played.
Since this is mainly to limit songs that have gotten annoying, and most of the songs that get annoying are the long ones, can something be implimented that the length of the song be considered in a filter, so that a spammer cannot request 2 20 minute songs within the same (say 10) song time frame? I for one can put up with an annoying song if it's short...

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If I were in human form, I wonder if that boy would want to see me again. ... ... but... I know...We'd never be able to be together...