Given The Portal Tapes/Portal were written not long after Focus, I was figuring they would resemble Focus, but they didn't. I was bored to tears.
As far as albums like Focus, I honestly haven't found anything exactly like it. Some people compare The Faceless, which I guess their 1st album, Akeldama, I find to be their best record, but I don't typically think of Cynic necessarily when I hear it.
You have bands like Obscura, Atheist (duh), Gordian Knot, Aghora and Spiral Architect among others suggested as "similar artists" on last.fm.
I would endorse Spiral Architect's "A Skeptic's Universe" as that record is quite good, although like The Faceless, I don't necessarily hear blatantly obvious similarities, but there are some still.