I like the dragons story idea, but there are lots and lots of people writing fantasy fiction, far too few writing about the real world of ambulances etc. Personally I'd like to think it would be far more than just the two books -what you do in your day -and night- job and the ability to write well about it is fairly unique and I hope you regain your previous enthusiasm for it. Could you not combine fiction and EMT experiences? Real life as a basis for fiction worked pretty well for the likes of James Herriott over many books.