I mean 10 scrap is way too generous. You get so much of it in the begining, I feel as though some alternatives might be:
50x Mechanical scrap
or
40x Mechancial scrap
3x Iron

The manufacturing end for engine ingredients and needing assembly machine makes it harder, just using mechanical scrap which you already have loads of seems abit too easy.

Hi Littlefinger, we've done the math and the recipe as it stands is fairly balanced, but we've added a startup setting so you can modify the balance as you see fit. The amount of mechanical scrap produced has been reduced slightly across the board as well.

Oh thanks Saf!

It's more just the ease of use with how much mechanical scrap you obtain.

Versus having to setup entire elaborate automating assembling factories.