Disgaea 4: A Promise Unforgotten was one of those games whose complexity sometimes got in the way of enjoyment.
Nevertheless Disgaea is something of the hardcore RPG fans dream, and if you're into this sort of game you'll be glad to know Nippon Ichi have both Disgaea Dimension 2 and Disgaea 5 in development. The former is a "true sequel" to the original Disgaea: Hour of Darkness and follows Laharl and Etna once again. The game will mix elements of the gameplay systems of the original game as well as those found in Disgaea 4. It's due out in Japan on March 20 next year, exclusively on Playstation 3, to coincide with Nippon Ichi's 20th anniversary.
Disgaea 5 is a separate titles, but no details have been confirmed at this point in time.