[LAU] q: percussion piece

I'm working on a percussion piece where I've generated the score by hand, then had a percussionist perform all three parts (instruments) of the piece into a midi file. I've got a library of around one hundred or so samples I designed that I want to experiment with i.e. arbitrarily select samples to play in order to build a little percussion ensemble for the piece. What I'd like to do is have ONE program (if possible) where I can import the .mid file, create a multi-sample instrument (yes like a drum kit) and assign any of my percussion samples to the key/note being played where I can tune, pan and adjust volume for each key/note. I'd prefer to do it all 'under one roof' if at all possible. I looked into LMMS but don't think it really does what I need it to -- besides, the LMMS documentation is very poor - so it turned me off to researching it further. Can any one point me to a simple one app does all environment on Linux where I can simply import a mid file and make a multi-sample instrument? I haven't worked with midi since my Silicon Valley days so I haven't been paying much attention to midi tools in Linux. Any help is appreciated. thanks in advance! KIM