New SIM800C Project Help

Hi

This is my first build with a SIM800C and 32u4 , I would appreciate it if someone could have a look and see if there is any mistakes.
Project will read voltage on A0 and then send SMS to few numbers when below 2v .
I have only ever used the SIM800l with Arduino UNO .
Now i want to have everything on one board no more loose pieces and have JLCPCB build the entire board .
I am afraid if something is wrong i will have many coffee coasters.

Thank You

Rocco