Nooooo to the salt. After being in salt for more than 10 days, the bettas kidneys start shutting down.
I don't see why snails would be bad. They don't eat the babies and they clean up.
What did the places on the net say about why you shouldn't have them?
All I have heard about bettas, is that the people who I knew who bred them did a 25% water change every day, and fed them daphnia.