Great game but the random power ups make it impossible to create cohesive synergies.
If you want to keep the 4 random skills, maybe make 4 categories of skills: Attack (damage, rate of fire, range, etc), Visibility (scorching vision, slow down, overview, etc), Getting Hit (invulnerability, thorns, etc), Misc (first aid, increased health, etc).
Or some other grouping just for consistency so players can focus on creating aggressive builds or defensive builds, technical builds, etc.