Sure.
I aim to have our interview cycle take under a week, although in honesty, I think it takes about 10 days. I often take on a little more work myself (especially in the phone screen) if I believe it helps speed up the process and saves others time. Speed is important. Keeping momentum during hiring really makes the experience better for everyone.
For background, I work for a startup lab in Boston (we build prototypes that we spin out into companies). We're about 35 employees.
Oh, and let me start by saying that while all the pre-interview work you've listed above does take some time, the real time cost to hiring is from the interview process itself since it involves multiple people.
1.) Resume review: 3 minutes. It took longer when I first got started. I used to agonize over "call/dont-call." But you'll usually have a gut reaction to the resume, and you'll eventually learn to trust that (for better or worse ;-)
2.) Code samples/Exercises: I don't bother with them, although another manager I work with uses them to good effect. Unfortunately, they can add between several days to a week to the process, so I do a more involved phone screen instead to keep things moving.
3.) Phone screen: I spend up to 90 minutes in the phone screen. This seems to be fairly unusual. 90 minutes is a lot of time to invest, but the key is, I only spend that long with the candidates I think I'd like to bring in. The call is setup so that I can cut it short at any point. Even still, I spend a lot of time here. I get to know the candidate, feel out their passions, and actually have them write code, live in an EtherPad derivative while talking to them.
4.) Almost 6 person-hours. Our amazing director of talent greets the candidate, and spends 15 minutes giving them the lay of the land, paperwork, etc. Then two different two-person teams interview the candidate for an hour each getting to know the candidate, sharing what life here is like, and working on one large technical problem. Then our CTO and I spend 45 minutes with the candidate answer questions, talking about the direction and strategy of the company, and gauging their interest in what we do here. Interestingly, the interview process we've been using on the UX side of things spends more time working on a single practical exercise (using computers, not whiteboards) and finishes with a broader meet-and-greet. Since I'm constantly experimenting with this process, I'm planning on trying a variant of this on the software engineer interviews as well.
But I aim to have the whole process from resume review to offer letter done in a week.