I really want to. As soon as I level up my skills sufficiently, I'll take a crack at it. Not nearly enough 3D platform games in the world.
<removed bit of spur of the moment related to wanting to make a game like what you described. Too many projects already started, can't really start more now.>
Your idea is just kicking ass in my mind now. Do it, please.
Anyway, to contribute with ideas I'd like to see/realize:
- A sort of reverse-shmup, where instead of you being the sole ship that can destroy the menace, you are the "wicked dictator"/"mad scientist" or something who has to build and deploy those ships that go towards your then enemy. I'm thinking of some sort of RTS, in which you command the building of ships and the research of newer, better ships and weapons to delay or destroy the so-called savior, at least delay him until your (or the stage's) big-ass ship is ready to take on him - or delay him a bit more, so you can run up to another place and start another stage.
- Some 2.5D game like a deathmatch of paper ninjas, in which the ninjas could fold themselves origami-like into many things like birds to reach high places or envelopes to pass below doors. Swords would cut up and thrash the killed ninjas. Cardboard and rice-paper houses which can be cut are also part of the idea.