Should slow dancing be base game instead of just part of one pack?

I think they should have done it like

Base game : basic slow teenager disco dance you know the type where sims just hug swaysway kinda like one in ts3
Wedding pack : the couple dance they did add
additional update: Couple Rumba sim for Jungle Adventure
additional update 2: Couple club dance for Get Together
additional update 3: Couple fire dance for Island Living?

basically: this couple dance should not exclude possibility of other couple dance styles existing in the game
just do it in other styles for other packs and/or base game