You might add a keyboard control option. The mouse-follow control is problematic with flash since things get funny when you move your cursor outside of the game window area - which tends to happen a lot since you frequently move the paddle to the very edge of the top/bottom.
Also, what other guy said - this is Kong, games must have upgrades! Bigger paddle, more lives.. flaming balls?
I kind of like it, but would suggest:
1. I don't like this 'You lose, game over' thing; just let me retry the level.
2. The up key to retract the harpoon thing doesn't work for me.
3. What are the extra harpoons you can buy as an upgrade for? I can't throw more than one at once, and I've never seen one of them break or be lost (though I didn't make it past level two)
4. The music is too.. jazzy and lively to be good fishing music. Also, it seems to be a pretty short loop, so it gets old quick.
Random ideas:
1. How about a fish radar type upgrade?
2. If there aren't already - different fishes at later levels.
3. Maybe you have to upgrade to a stronger harpoon to catch those bigger fishes; it can break the small ones
But nice start, hope we'll see a sequel or updated version :)
The basic design is okay, but it lacks any.. well, any point. You can make up your own - e.g. fill up every property with a fully upgraded bank. But that's not too fulfilling. There needs to be some end point where you win; otherwise it just turns out to be Whack a Mole (repairing all of your properties), but it doesn't speed up and there's nowhere to go from there.
 "Pong"){kind=icon}
 "Legend of Rifle"){kind=icon}
 "Fishing Deluxe"){kind=icon}
 "Real Estate Fun"){kind=icon}
 "Relic Of War"){kind=icon}
 "Zombie Situation"){kind=icon}