Hmm, I played twice, once the bunny and once the squirrel for comparing purposes, and think this really needs sum polishing:
- Games which base on speed like this need to give the player every possibility to see ahead in order to recognize obstacles early. At full speed, the character should be at the top of the screen, not at 1/3rd from top, 2/3rd from bottom, the 1/3rd is going to waste for its information isnt needed any more in the game. So, you should let the game "scroll up" with increasing speed or be there permanently.
- Second thing is "level knowledge": You have only one level, but for it consists of the same images again and again, the level is extremely hard to memorize. If you want a non-memorizeable map, you should avoid these small green bumps, exspecially if they go all the way from left to right side of the screen. Their colour is terribly even to the ground, which makes them hard to evade already at half speed. This goes for the squirrels bonus arcorns, too.
- You are doing the same error I see in several other games, too: Your game currently is based on retrying to beat your foramer time. To do this, you got to put your controller (the keyboard) away and grab your mouse, click the retry button, then put the mouse away, and grab the keyboard again. Seriously, we players HATE to have to do this. Either make the game fully keyboard-compatible, or fully mouse compatible, OR permit the use of w a s d as an alternative to the arrow keys, but dont force us to do this kind of jogging ^^
- Oh, and there is one last "pro" thing: This game is played out of the sight of the player, means, left button means the character goes to its right side and right button makes him move to his left side. There are several games where this is exactly opposite. To fit the needs of these players, you could add the option to invert the left <-> right keys
All in all: Add several levels, add a minimap (maybe as a collectible to obtain after 1/3rd of the map) and remove some of the small bumps, and this will be a fluidly playable game.