I see alot of people talking about how the crafting is a bit redundant in the game, maybe a solution could be to make each crafting shape limited, then have a set amount of "generators", so you could farm two shapes at a time but not all three. I'd think this would make the player think more about what resources they are lacking and hence be more engaged.
Also, maybe allow rotations in the crafting for different effects. For example, making the rocket in a diagonal fashion would make three smaller, weaker rockets, and turning it horizontal would make a weaker homing rocket.
Obviously don't be too pressured to add everything and anything, do what you want to do. This game has gotten me to yap and you should be proud(?) of that. :)