If only note input is what you want, ProTracker will support it. I use 2.3d personally, with an Akai MPD26 pad controller.
One instrument at a time though, don't expect to be able to do fancy stuff like keyboard splitting or something like that.
Some of the key messages are mapped as commands on ProTracker too, for example, for changing instruments or for transport control (play, stop and record).
Pretty much any Amiga MIDI interface is the same. All the ones I have have 1 input and 3 outputs and in many cases you can usually switch these outputs between OUT and THRU.