I would have to agree with the client that tightly integrated is a good thing, and I've personally previously rejected the options I mentioned because of that very reason ... but then I'd also have to agree with Howard that trying to totally exclude Admins etc. is a bit odd (especially as they have access to information which is far more sensitive than what you enter in a reflective journal!).
Good luck finding a suitable solution - I think it's always good to consider all options, even if it's only so that when the client later turns around and says "what about option xyz" you have already considered some of the pros and cons of it!
Cheers,
Rena