that's a very slippery slop .. i suspect a lot of users would be put-off by ranges that kept changing on them as they added/removed other facet constraints -- one minute you are seeing ranges like 0-10,11-20,20-30 and then you say you are only interested in red products and now your ranges are 0-12,23-20,21-30 ... ? ... that might be a little confusing.
Very good point.
picked by a person and stored in metadata
This is my current design.. I think I will stick with this after your comments, thinking about it more, and the troubles that I'm having to get it just right.. Plus, the inflexibility by not allowing me to specify the label in different ways like I do or can do now. I'm trying to make it as automated as possible being that I have limited human resources. However, I did make it easy to update and regenerate my facet config files so it wouldn't be bad now, plus the ability to use me own labels for certain buckets is nice. Thanks