Hi
You’re not bothering me; I’m always happy to hear suggestions.
I don’t think giving a productivity bonus is a good idea. An assembly machine can produce a lot of items, including the science packs. I think that would be unbalanced.
Furthermore, machines that have a productivity bonus have specific functions, not generic ones like the assembly machine. To me, the upgrade makes sense in terms of crafting speed, as 1.25 is low compared to the others.