Lots of people want tap/hold but I think it's the most boring solution. I'd really love to see a change to Eclipse give Mirage more synergy with her abilities, which already have the theming of creating light.
Imagining a version of eclipse where it defaults to the DR mode, and then you activate the damage buff by casting, say, Prism, which creates a cool synergy where you basically switch into glass cannon mode briefly, would be a lot of fun. And it would inherently nerf the Helminth version, because other Warframes can't use Prism. Or some other alternative version, idk. But something more fun than just tap/hold pls