I probably wouldn't have a meeting room, preferring to save the space for a big workroom. That has a threefold effect. First, you have more space to use for actual work. Second, you have no secret meetings larger than two or three people. Third, everyone has to be involved in any meeting, so you have pressure to have fewer meetings.

The important thing I want to encourage is happy and accidental teamwork. Provided you have a healthy team, I know of no better way of accidental teamwork than having everyone work in close proximity. (Obviously, if you're working as individuals, you'll have concentration troubles. I'm a strong believer in pairing, though, so it tends to work out nicely, once you get the hang of it.)

The extra offices are there for private phone calls, one on one meetings (performance reviews), and private e-mail or research. They're temporary; you wouldn't use one for more than an hour or two at a time. (I like the way the O'Reilly offices in Sebastopol are laid out — there are offices and group work areas. If you want your own office, you can have one. It's in the middle of the building, though. The group work areas are along the outside, by the windows.)

Figuring out software and physical setups is trickier, but if you want the happy collaborative accidents, you need to standardize on one or two configurations that everyone can work with productively. It's more important to work well as a team than to use what you were most comfortable with on your own.

There are legitimate and important ergonomic considerations that may come into play, and those have to be taken seriously. In those cases, you may need special equipment, but that's motivated by the genuine need to include someone in your team, not to assuage someone's preferences.

The sound proofing is mostly for noise, though having a different atmosphere can be nice. Lots of companies already have different atmospheres for different groups. If you visit O'Reilly headquarters, you'll notice that customer service feels very different from HR and both are quite different from marketing, not to mention online publishing. (For one thing, there's a bookshelf full of foreign translations just outside online publishing, while the marketing department has lots of posters and end displays and a whole table full of pamphlets, mailings, and geegaws.)