Future idea - Pre Industrial Realism.

[eradicator]

after all, most early smelters have it mixed with the ore, and work only for a specific type of fuel.

Now that sounds like a better solution.

1. Factorio allows infinite exponential growth only at late game, but they are many limiting factors during early game.

Maybe i worded that poorly. I don't mind *natural* limitation, like..enemies, or very expensive buildings. But Factory Town made me realize just how f****** annoying *artificial* limits are. If i have the raw material to build 200 furnaces, i want to be able to do that without somebody telling me "but your furnace control limit is 20 hahah!". Just a word of advice about limitations :)

But here is an idea: maybe you can make early workshops with crafting speed=0, and make worker a "module" that adds +X crafting speed (instead of the *(1+X%) )?

Pretty sure you can't do it directly. And hacking it in requires code wizardry skill level 99 because module interactions do not trigger any events.

What is the general attitude towards using content from other mods? What i need to do if i want to use parts from other mods?

Read the licenses. Carefully.

This. Lucky for you the factorio community is rather open and lots of code has permissive licenses, and if something you want hasn't, then asking never hurts (also telling the other person "thank you" even if the license doesn't require it is a nic gesture.) Graphics tend to be more strictly licensed. There's a "graphics request" subforum where you can try to get someone to do the work for you, but random strangers probably won't do 20 large and complicated buildings on first request (i think @archangel666 has a thread somewhere with freely licnsed graphics he made but ended up not using himself). You should concentrate one building a working prototype without graphics first anyway, which will then increase your chances of getting someone to do the graphics.