It depends upon a number of variables. If you are bringing someone in at a very senior level (e.g. partner), then they will require more disclosure. When you are hiring an employee, a lot depends upon how important they are to the organization. You do NOT need to give away stock. You need to compensate people fairly. I am a firm believer in making the entire pie bigger, by allowing greater ownership by those worthy.
Recognize that your equity should be highly valued. (Most people do not always value and appreciate the value, or at least don't put the same value on it that you do.)
With regard to salaries, I think complete transparency causes jealousy and problems at work. As an organization, you are motivated to pay what is necessary to fill a position with the best employee. It is a value proposition. I will hire a "9" over a "10" if there is better value from the "9" or there are other variables, intangibles, etc.
Without question, some employees will believe they are worth more than others. As management, you have to make that call. A "flat" organization only works so well, and in certain environments. Compensation is a very sensitive issue. I suggest using discretion, and depending upon your organization, structure, experience, seniority, contribution of the employee or partner - all of these things will weigh in.