I don’t use FreeScan, so I cannot guide you on exactly how to program, but I can give you some general tips.
For sites if you are just interested in MCSO East, and you can receive the Thompson Peak site very well, then you can get away with only programming that site as it will carry most of the East talkgroups all the time. This is the main East site, and other sites in the East Valley are smaller filler sites that don't carry talkgroups unless a unit is affiliated with them. If you can receive other sites (Bronco Butte, Mesa, Chandler, etc) you can also program these especially if you get a much stronger signal than Thompson Peak. If you won’t take the scanner mobile, you will not need the other main sites (White Tanks and Central Court) as you probably won’t receive them very well from Queen Creek.
For talkgroups, program everything you want to listen to. I would for sure program all of the Sheriff East talkgroups. Program for “Scan” mode rather than “Search” and you will only hear the talkgroups that you program.
To identify when the dispatcher is speaking, you can program Unit IDs. You will also need to set up the scanner to display unit IDs, and set how you want it to display. There are 3 display modes for the 996XT. You can label the dispatcher IDs in the software. As I am typing this, Unit ID 52980 is the East Dispatcher. There are probably many other dispatcher IDs, but I rarely listen to MCSO so I have not documented others. Once you get it set up, you will see unit IDs as they talk, and you can make notes and update your programming. Some other Unit IDs that you might be interested in are FOX (helicopter) units. Here are some of the FOX unit IDs that I have logged in the past – 46718, 46719, 46805.
Hope this helps.