Cool game and challenging.
However I have some problems.
Most of the weapons are useless and since you can always buy a better weapon you don't have to use them. After I got my first laser I never bought anything else. Ohh and never used upgrade. Since I had infinite amount of cristals (because of the level limit) I spent all of them on buying in the bonus shop. It is slow enough to pick the thing you want. (Most of the time.) The ship guns are useless, at least very inaccurate so can't hit many times.
And same with the skills. Not enough points to max all out so I had to choose 1 to max. Before I had enough points I always used Grenade and MP Plus. After I maxed my level I respent my points to MP Plus and Wall of Fire. I've tried every possible spent and this worked best for me. (Obviously not every single one but once I maxed every skill, used it and then respent my points on another skill to max.) Ohh and the rest was spent on Speed and other Passive skills. (Not on the drop rate buffs.)
I think that the Ship points are also useless I spent all my points on hero damage.
So it could be better because most of the content was useless for me, but I enjoyed very much. It is very addictive. I wasn't able to stop playing. Just keep up the good work. I love your games Berzerks.