for the voices, I think things will get better and better with the future NT2 and V6 banks, but it's also the concept of Project Sekai that you start with simple v-synth and can make various type of songs. Since it's also a game with live-development, it was the preferrable way for them, and again, I feel with NT2 and V6 engines there will be more improvements ^^
as for the codes, in Japan there were codes (to use only with the japanese version of Project Sekai) given both to regular and limited tickets, and for the overseas release, I've heard that most of times the codes (for the english version of the game) were available on some tables at the theater entrance
as for the codes, in Japan there were codes (to use only with the japanese version of Project Sekai) given both to regular and limited tickets, and for the overseas release, I've heard that most of times the codes (for the english version of the game) were available on some tables at the theater entrance