The funny thing is, the original story is hugely complicated and genuinely thrilling, but all the shortcuts they had to take in this version because of time constraints ended up making it predictable, and that's a shame.

You echo my feelings on this exactly. I read one review that said they liked the change because it illustrated that homosexuals in those days were very good at putting on an act, living double lives and having double identities and therefore were suited to being spies. Which is all true, but with Guillam in this adaptation, you get the feeling that he's really not suited to the job at all. Cumberbatch talked so much about getting in character, even going to North Africa, where (in the source) Guillam ran his own team of agents. None of that was even mentioned.

Just disappointed, although I think I would have liked it more if I hadn't gone in with so many expectations. Still a good film, just not brilliant.

I think that's what it comes down to for me. It is not a bad film, but it has nothing on the other adaptations and very little in common with the source material.