I have only just started level 1 of Rabbit Adventure, but I have absolutely now idea what to add next. Here is the link to download the level: http://www.savefile.com/files/105304 It uses the Forest tileset by Blade. Please play the level then PM me advice on what to add next.

Oh, I always have those sort problems with my levels.
Alright, let's first start off with why Devan is destroying the forest.
Is he harvesting lumber for some super wood robot? Is the forest the ideal place for his new industrial plant, and must be removed?
Once we get Devan's motivation we may get some footing on where the player will be sent next in the level. Let's say Devan was building an industrial plant. Perhaps part of the level would be the player trying to destroy the construction site's base so the building cannot be built.
I would also highly reccomend a puzzle utilizing the electroblasters. They're fairly useless otherwise.

Here's my original story planned for RA:

5,000 years ago, an evil king spread terror throughout the land. But his evil plan was stopped by a rabbit with a gun. In his last attempt to keep his evil power in the world forever, he stored his evil power in 5 sacred stones. Then he hid the sacred stones in the most remote locations on the planet. If anybody could obtain all 5 sacred stones, he/she would be able to go to the Pits of Hell, and be given the power to turn into a demon. Devan Shell, a turtle desperate to get rid of Jazz, searched the world frantically for the 5 sacred stones. If he gets all 5, he will have the power to destroy the world! Jazz needs to find all of the sacred stones before Devan does!

And the reason Devan wants to destroy the forest is so any Sacred Stones in the forest could be easily found.

I'm going to try really hard to make a good level pack, and when it's finished, it could be almost as good as Evilmike's Level packs.

Yes of course it will