Thanks for sharing your thoughts, @BratPak_Dog_Kamp! Our Appointment Book widget is relatively new, and we’ll definitely keep enhancing it with more features down the line 
You can see what we’re currently working on via the In-Progress tag (Topics tagged In-Progress).
I love your idea with SMS reminders — we have separate suggestions in this regard, so feel free to upvote them to stay in the loop:
- Send an SMS with a reminder about the appointment
- Send an SMS to us and the customer who books the appointment
Thanks a lot for your help!