There isn't any need for more than thirty planets/worlds even beyond 2021!
They say by 2025 there will be 500 planets since Mandalorian homeworld at this time in the star wars universe is an important player in galactic affairs it will probably be added early on.
My point is that more than thirty fully developed worlds would be pointless, not so many potential customers to be attracted by the great number of different worlds but the cost of development of so many worlds (intriguing storylines etc) goes then to the sky!
However I would like to see at least two Mandalorian worlds (including the greatest jungle world of Dxun plus its big brother, the intriguing Onderon) plus some water worlds (Rakata Prime anyone?) and of course some jungle worlds, particularly Yavin IV and/or Endor...
Kashyyyk (especially if paired somehow with the Trandoshans' world) could be a great addition also
Edit: however neither some Bounty Hunter nor any Imperial Agent did answer my speculation about the Mandalorians' presence in Hutta.