Hey! This thing’s got potential! Gee, where do I start?
Okay… first of all, and foremost, “Cut! Cut! Cut!” Go through every second of the film and cut away every second, every half-second, that does not move the plot (“hey! you actually have one!”) forward at an increasingly-frenetic pace. You will find “wasted seconds” scattered throughout the existing footage.
There are various rules-of-thumb for this, but they basically come down to “cut on the action.” Present just enough information to me so that I “get it,” then cut. Make sure also that you give me some kind of reaction from the character.
For instance: when we start out, we really don’t quite know who this guy is and what sort of world he’s in. Very well… let him be figuring it out along with us. But show some emotion: is he (over-)confident? Is he scared? He figures out he’s in some kind of a video-game. He notices something that will prove to be important (and to re-emphasize its importance, rediscovers it several times. Hence, we do, too. Good!) Cut! He sees a tasty prize! Cut! He grabs it. Whups! Cut! Starts to run. Wins some, loses some. (Reaction.) Cut! Along the way he figures out a creative way to kill-the-beast. (Reaction.) He throws! Cut! It lands! Cut! Beast gets (Steven) Spielberged! Cut! The cuts come faster and faster until the… climax. Victory.
You get the idea: producing the footage is only half the battle. Now, you set about cutting it together into a story and in that regard, split-seconds can mean a lot.
You’ve got a lot of things going for you now: no exposure-errors or framing issues… generally good shots throughout… a plot… a cohesive story-arc.
Now… If you do want to emphasize that he winds up “with no gem,” you’ll need to emphasize that with a few reaction-shots. When he spies it, we need a brief cut-away to show “he wants it.” When the ogre appears, a little bit more reaction when he finds he can’t get rid of it. Now a little bit of “I still want it, dammit” when he runs … so we know that, at this point, he wants to save both his skin and the gem. Later on, when he comes up with his creative solution… show his quandary (just a few frames…), then his sacrifice, then his victory (dead grue), then… his loss. Show the gem rolling through the door. Or, show the gem coming to a stop in a shot that suddenly turns dark as (we know… the shutting door…) forever cuts-off the light. We’ll know, thereby, that the gem is beyond the door. Go ahead and “lift” it right from Indiana Jones…
Great story. It’s gonna be even better. You’ve got a very-few shots to add, and a bit of tightening-up to do, and you’ll wind up with a very nice “yarn.” The simplistic animation doesn’t bother me: this is a yarn.