We totally feel you on the Unity UI troubles. We saved that portion of development until the very last day of the Jam, and well... Let's just say that we've seen the game load up in some very funky ways on different computers since we've released it.
Either way, interesting idea. What you managed to complete works well enough, and is fairly entertaining. Was there plans to have more obstacles to get in the way of the target that you would have to navigate through?
Viewing post in Task Force Kodama jam comments
Regarding obstacles, not really. The initial plan for the jam build included having variation in the trees (basically just randomising the scale on spawn as that would be relatively simple to do for the jam), and including variation in enemies in such a way that would restrict the player's actions; flying a missile above the treeline for too long while in range of a SAM enemy would result in your missile being shot down etc.
Also planned for the jam was to have two other attacks: mortars, which would spawn in the sky above your target and have to be flown in, avoiding obstacles in a manner similar to the freefall mechanic in the third Ratchet & Clank game; and air strikes, for which one would have limited control over the plane as it flies in, having to judge where to fly relative to the target and when to open the bomb bay doors based on the plane's momentum and the wind.
Longer term, if I continue to work on this, I would probably hope to add proper terrain generation and make the area fairly mountainous. Also get the spawning algorithms solid enough that the game didn't have to be locked to the same seed for every playthrough (unlocking the prng's seed at present would leave the very real possibility of trees spawning directly upon the player's starting location among other issues, possibly making the game completely unplayable on certain seeds).