I would like to suggest having a direct access to hire staff from the staff management menu. For exampe, today my guets were complaining about all the rubbish, so I went to check how many janitors I had. So I had to open the park managemet menu, click on the staff management menu. I only had 2 janitors, so I needed to hire more. Then I had to press ESC to go back, and ESC again to exit the park magement menu. Then open the hire staff menu and hire the janitors. Having a direct access would be much quicker. Something like this: