Remember when PSVita had the "Vita" Song Campaign (ビタッとソングキャンペイン) being a full-on DLC poll of sorts? Something similar is happening for PS4 Taiko no Tatsujin Session de Dodon ga Don. Announced and opening today (August 30) is the "Pittari Song 4 You" Campaign (ピッタリソングフォーユー キャンペイン). (ahhh the initials spell PS4, heheh I see what you did ther)
The campaign now starts with a poll (Bandai Namco ID required, get one here if you don't have) which asks for at most 3 songs you would like to be DLC for PS4-1. Once again, remember to use the formal names (i.e. no short form or nicknames) or risk not being able to be counted.
There, I filled one for myself too, even though I am not gonna buy a PS4.
"Pittari Song 4 You" Campaign Poll: https://analytics.bnfes.jp/enquete/pc/ps_4u_cp/