There are a number of adventure sailing schools that run with varying degrees of success. Mahina Expedition ( http://www.mahina.com/
) is one of the better known, longer running ones. The systems idea is an interesting one and is a niche I haven't seen. However, it seems to me that you will need some degree of hands-on to sell the maintenance idea, even if it is changing oil and impellers on engines, bleeding fuel lines, flushing watermakers and changing membranes, cleaning strainers, changing water filters, lubing furling gear, going up the mast, cleaning and sealing coax connectors, perhaps some splicing. Remember air conditioning and diesel heaters (forced air and hydronic).
One issue will be that many people will already be locked into brands (someone with a Village Tech watermaker may not believe the applicability of messing about with your Spectra).
Communications is particularly diverse. I think you would need to carry gear for voice and data for SSB and Iridium to address client desires. Don't forget to figure in the cost of air time for the satellite practice.
It also seems to me that your market will require some customization. Your skipper should be able to teach things like celestial navigation, dead reckoning, pilotage, close-quarters boathandling, and talk about anchors and anchoring objectively and without offending anyone with deeply held religious belief in the virtues of their anchor of choice.
Your market is likely to be dominated by people with or looking at new or newer boats. Mahina is - I believe - on their third Hallberg-Rassy to stay current.
Depending on where you are planning to sail you may have to observe Jones Act requirements. If you are operating internationally you'll certainly want your captain to have a USCG Master's license *AND* an RYA Yachtmaster.
Per the above comment, I'm not sure you can operate effectively without two crew: your captain/instructor and a hostess/cook.
Systems are interesting, but it sure is biting off a lot. I honestly wish you luck.
If you go for it and run a celestial course I'd be interested. Remember we have to be far enough offshore for a real horizon -- none of this artificial horizon hooey!