Wiring multiple sirens, strobes, etc

Hello,

I'll start off by saying that I really have no idea what I'm doing... but trying to figure it out :-) I have a Konnected Pro board and I'm trying to wire up 2 x Interior Sirens, 1 x Exterior Siren, 2 x Strobes, 1 x Fire HD10 Tablet and 1 x Piezo Buzzer.

I've identified that I'll likely need an external power source to run all of this so I went ahead and purchased the following off Amazon:

https://www.amazon.com/gp/product/B06VWV5YCH/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

I've also identified that I'll need some 12V relays so I've also purchased the following off Amazon:

https://www.amazon.com/Youngneer-Raspberry-Arduino-Channel-Opto-Isolated/dp/B07WP7C8ZD/ref=sr_1_4?dchild=1&keywords=12v+relay&qid=1606934397&sr=8-4

I'm created a diagram (attached) of everything and I was hoping that someone could check it to make sure it all makes sense and potentially provide guidance on making it less complicated if possible.  I also think this will be helpful to others as I couldn't find anything else that really described how to do this in this level of detail. Thanks!