The fairlight CMI's something I'm pretty familiar with myself, Mr - totally adore certain records that utilized it, like 'The Dreaming' by Kate Bush, various 80s pop music, and also a Mars Lasar track for Parry Music called 'Exotica', one of the most beautiful library tracks I know. It's an early digital sampler and was pretty revolutionary for the time, capable of some interesting samples & sounds, usually pretty crystalline sounds or big industrial rhythms, sound effects, etc...
Honestly wish I could find more library that used it. I'll look up this Francis Monkman though.
Back to innovators, though... Would David Vorhaus count? I read he was part of the group White Noise, which is pretty cult and acclaimed, and according to Discogs, he invented the 'Kaleidophon' - 'an electronic double-bass-like instrument that he uses on some of his recordings'. [Interestingly, he started out playing classical bass and also made some straight up MIDI/PC-game sorts of records later on.]