Suggested model setup for appointments analysis?

Hello,

Im wondering if anyone can recomend a 'best practice' for modeling appointments data. 

Resulting model used for:

• Analysis of kept, missed, cancelled appointments by either created date, or appointment date
• Analysis of resources attached to appointments, counts of types of appointments by resources, etc
• Analysis of appointment created by particular users

Current Table Schema:

• Appointments table, that acts as the hub, each appointment is represented by 1 (or more rows)
• If the appointment is rescheduled, a new row is created and the previous (cancelled appointment) is marked with a cancelled flag. 
• GUIDs/refrences to other tables containing resources, users, event types, etc. 
• Create date as timestamp, appointment date stored as 2 columns (string date) & (string start time) example( mmddyyy) / (hhmm)

Current Model:

• Appointments serves as hub, with lookup tables for the resources, users, events as spokes. 
• Transform on the appointment date to a standard date/time column
• Standard date table linked to the appointments table.

Issues I'm trying to solve:

• I can't easily gain many insights from the data without complex DAX for EVERYTHING. For example counts of appointments created this month.
• Because the date table can only have 1 active relationship with appointments, again i have to use DAX to specify if it should use the relationship to create date, or appointment date. 
• Generating simple outputs, of say appointments kept by month, or appointments scheduled by month are seemingly more complex then I feel they could be with a better model. 
  • Example: I'll have to set the active date relationship, filter the table by expression for rows i need, count rows + 0 to generate usable data. 
• Because of all the DAX and switching relationships, most drill-down, or interactions between visuals just wont work. 

I'm sure somone has tackled this challange. Any suggestions? 

Edit: Pictures of model....