A) You will not earn a "solid income" as a flying instructor. You might be lucky enough to earn just enough to scrape by on.
B) It is good experience as a first job in the industry. I would imagine it's quite different to a transport job, but it's still a job, and has all the pressures and so on which come with the territory.
C) No idea first-hand how much the airlines value the hours, because I haven't got around to applying to them yet myself. But I know plenty of instructors who have gone on to airline jobs.
If you want to instruct purely as a way of getting to the airlines, then I would suggest forgetting it. It is hard work, long hours for not very much pay. If you resent the job, you will be unhappy and will not be able to instruct well. This is simply not fair on your students. (Imagine if your instructors at Oxford had this frame of mind.....)
On the other hand, if you think that instructing sounds like fun and is something you really want to do, even just for a short period, then go for it - it is incredibly rewarding, and hardly a day goes by when I come home from work having not enjoyed myself.
If the idea of low pay puts you off, perhaps consider doing the fATPL by the modular route and saving yourself the equivalent of a year or two's salary as a flying instructor. The biggest argument for the integrated course (and I'm not sure how valid this argument is anyway) is that the major airlines are more likely to recruit you straight from an integrated school as compared to recruiting you straight from a modular school. But if you're looking to instruct for a year or two anyway then you won't really care about being recruited directly from OATS by the majors. After a year or two of instructing and a couple of thousand hours, which school you trained at stops being relevant.
FFF
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