Do we only get one 2019 New Year ticket?

Yes unless you buy the happy bag, $116 bucks for all three and you get 29 guaranteed sparking units which include gogeta, new broly , new batch of units (except Beerus)

The blue bag is the cheapest and provides 2 guaranteed sparking tickets, the silver bag is a medium sized purchase and offers 6 tickets and the gold bag offers 20 tickets but costs the most amount of money. You can only gain one ticket by login in within the month of January 2019. The rest of the tickets can only be gotten by purchasing them with real money.