Unless one of those 14-y/o's is a clone with accelerated growth, then there probably won't be any. The only "cliches" I'm after are the "hard-bitten mercenary/salvage/ancient-alien-artifact-hunting crew" cliches. Kinda like the crew from Alien Resurrection. They get "conscripted" (read: press-ganged) into the linear-plot's "main mission" by the game-world's Imperial-type gov't. "We have whole hard drives worth of charges against you. We'll toss you all in the cacky if you don't cooperate and go on this ultimately suicidal mission." That stuff.
Forget about the shooter elements. Play a game called Starflight
. Most of the game consists of exploring systems and landing on planets and exploring those planets in a rover. Combat in space is real-time, arcade-style shooting of lasers and torpedoes to wear down regenerative shields and ultimately the hull.
Now think about FF's ATB system replacing the arcade shooter combat, where fights are initiated either by random encounter or when the player's sprite and an enemy sprite collide. The fights never take place on foot, only in space or on the ground in the rover. THE REST OF THE GAME WORLD FREEZES IN PLACE WHILE A FIGHT IS IN MOTION, WHICH MOVES FORWARD STEP-BY-STEP. No arcade action, no resource management or tower defense, just an RPGMaker-type JRPG with sci-fi sprites.
If the idea is really this hard to express, then I'm not going to bother trying to explain it anymore.