On the Hourly Sales Report when you run the report for a time period like "last week" the report separates out day by day.  When you run the report you should have the option to consolidate the dates so you can view the averages over that time period.

Instead of including Service Charge in the toggle for Tax Summary under Settings>Printer Configuration>Front End Recipt, crate a separate toggle. This way you can turn it on or off depending if you actually have a service charge set up on the Store Settings of Back Office. Picture included shows LEFT with Tax Summary, RIGHT without Tax Summary.

Please the function to create a check based discount that could be applied to a tab or tabs. That discount would be a set amount and would expire after the set has been used up by tab.