180 Litre Fish Tank Stocking Ideas

What I already have - ( In my 50 litre )

5 Neon Tetra
1 Molly
4 Swordtails ( 1 fry )
6 Platies ( 5 are fry)

What I want to add -

5 more Neon Tetra
7 Serpae Tetra
4 Peppered Corydoras

Can I have anymore fish?

If so would I be able to have a shoal of some type of Rainbow Fish? Or would I have to swap out the Serpae's? I've bought the tank and will be filling it up and cycling it in the next two weeks.

The tank is 39" Left to right & 15" Tall and 15" front to back.


Thanks for reading :)