Honestly, I can only speak for myself, although I think:
* there are already high-quality commercially available solutions -- oh, and also Tarrasch Chess GUI v3.10 was just released too!
www.triplehappy.com/News.html* each added filter complicates the front end and back end
* there isn't enough data to merit a rating-based filter -- but I don't know, maybe other staff feel otherwise
* very few developers have any of the Masters DB and I can't commit to it (I don't think I have any of it although maybe I could make test data like it if I had time)
