>>718896225 (OP)
>Does /v/ have any hope for the Disgaea series?
No, and neither do I have hope for any other NIS series at this point. People keep asking for return to 2D, but after constantly underpaying your sprite artists (and thus having fucking two major batches of resignations, one during Disgaea 3 development (that basically forced NIS into portable market for a few years to train new talents because they couldn't handle the cost of development for seventh gen) and another after Disgaea 4's development (because NIS still underpaid their staff after moving to high-res sprites)) it makes sense to just keep minimum amount of sprite artists for gacha Disgaea while hiring cheap 3D animators for literally every other NIS game. It sucks but they have no money to spare.
>What changes do NIS need to make to restore peoples' faith in the series?
Honesty? Try to make another hit and turn it into your cashcow for milking money while letting Disgaea rest. They did it many years ago when Marl Kingdom was carrying their ass until Disgaea 1 sold well enough to become their new main IP and letting Marl Kingdom retire. Disgaea is just overdone as a series and it's clear that devs are struggling to keep it up - move from 2D to 3D, intentionally cutting content and aggressively selling it as DLC on Day 1, cutting corners left and right during production by removing some features and guest characters, etc.
NIS is also unable to make a cast and story as good as in original one, so Laharl/Etna/Flonne keep carrying the series on their backs (they're the only ones who got sidegames like DD2, Infinite and sort-of Prinny games, plus D1 chars had canon presence in D2 and D5... even if DD2 was a good example as why you should keep the original cast alone and without direct continuation). Maybe it's because the Netherworld setting is just overdone, so I dunno, make an Angel cast and develop Celestia as a setting?
