It must be something in the air - we've just had a major garden facelift by a local landscape company (kept wife busy and she loved spending a small fortune on it), we considered a fire pit and a new sunken seating area - finally decided that we wouldn't do this suggestion from them it this year, but perhaps consider it next year- if all things were equal and the garden gets the use generally - which for what was a great early part of the summer it has been.
Let us know if you decide to do it and how you get on with it.