I was a Town Commissioner for 6 years of a small town (population ~640, but we're also the County Seat, so our daytime population is over 3000; exact number dependent upon how many people have jury duty that day)
Due to the limited staffing, I'd recommend that small municipalities only collect the data that they're being asked for or obligated to provide, and not attempt to guess what data might be useful to people in advance.
In our monthly newsletter, we list crime statistics, breaking them down by general category and if they're in a residential area or downtown. Originally, we just broke them down by type, but then someone started asking if it was downtown or in one of the neighborhoods.
We report our income and expenditures on a monthly basis, based on the categories that are defined in our detailed budget, along with the status of all cash accounts (amount in the accounts and status of collatoralization agreements).
Due to our small size, we've had to take a number of measures to mask some data. For example, when we moved towards being self-insured for health insurance, we consolidated line items that had been in each of the departments. The reason being that we had a department with only one full time person, and so if any money came out of that item, we felt it may leak too much information about that employee's health. We also have each employee as a separate line item, so it's possible for anyone looking at the budget to determine an employee's pay. It's doubtful that a larger municipalities would have these issues to be concerned with.