I don't want to sound like I'm badass or anything, but I found the game surprisingly easy. :)
The upgrades are cool - albeit a little to few - and the laser gun sucks bigtime. It shoots only once in every while and it's damage is not SO devastating in comparison to what the rifle can do - in a eye-o-meter, the rifle's DPS seemed quite larger than the laser's - at least for the heavier vehicles. Laser is devastating on bikes.
I really like the concept, specialy so being a passionate biker myself. I can totally relate to the "Only me and my motorcycle" feeling. :)
Game is simple, yet loads of fun.
Keep it up, bro.