The notion is rather straightforward, and would be extremely useful in various context, especially for Space Age.
- Enable multiple filters (equivalent to inserters) - being able to split more that one item will be extremely useful for mixed belts and sushi builds
- Allow to set blacklist vs whitelist (equivalent to inserters) - being able to exclude particular items would also be fantastic
- Set filter (signals)
- Allow to control input and output priority via control signal (negative=left, 0= neutral, >0 = right)