We always could use better vortex function. Or, rather, a universal teleportation animation (if you can think of a better one than the vortex) that will suit anyone. Like, I don't know, take character sprite, slowly make it black/gray/any other color depending on settings and split into pieces that disappear while flying away. And vice versa too, when the sprite appears. And with ability to control how fast all this is going on.
I also want a better (prettier than via menus) way to change party members outside of usual gui, ie during vn scenes.
Other than that, I just need better triggers to run labels for events and advance/finish quests, right after next day for example.
And of course we need SE. A good SE.