LM350 is rated 3 amps. Requires 2 additional resistors to set output voltage to 9 volts.

 

There are different 78xx voltage regulators. Check the datasheet.
If you are going to buy higher current 7809 then you may as well use the same one for all of the outputs.

L78S09CV is rated for 2A.

https://uk.farnell.com/stmicroelectronics/l78s09cv/ic-v-reg-2a-9-0v-78s09-to-220/dp/1087138

 

Diodes are to be kept for the reason of reversed power connections

If it's still not clear, those diodes on the output will not protect the load against reverse polarity.
How could they?
Reverse protection has to be at the load, not the source.