Sarah, I can start with a few answers. About tasks on the timesheet, each overlaying task will take a new line on the timetime. The only way to put all on one line is to make sure that the timelines of each task don’t overlay. Milestones aer always on the top or bottom as a callout. Tasks can be either task bars or a callout.
There are lots of options for formatting the task fill and text. Use the Format tab that shows while selecting the timeline view.