You don't understand WHY people have modpacks that have machines that do similar things is the thing. Every mod gets it's job done in a different way. It isn't literally mods that do Identical things, (IE, having two mods that add electric engines or whatever,) it is different ways of getting things done. Thermal Expansion machines make for nice, compact builds that typically work slowly. IC2 machines make for larger setups that work very rapidly. To each, their own, but everything you say further shows you just looked at mods lists, looked at the basic functions of what each mod does, and then didn't fully experience the other modpack.