I'm not talking about the theme, I'm talking about the game design. Flower was built to be a serene game. Litterally all you do is fly across a field activating flowers, gathering petals, making a larger and larger petal mass, until your finished activating an area.. It's a fun game, but the level design is hardly the kind of manic roller coaster ride. NiGHTS flying through rings in a field, without the unique level design gimmicks, perspective and game play shifts.
The flat, open areas and clunkier control set up just wouldn't be NiGHTS, I don't think, and I don't see how the controls could work in the kind of terrain and level design a NiGHTS game should have.