About 40 hours into my save, I realized I could use the "foundation" blocks as a way to organize the factory since everything snaps to a grid when you place stuff on top of it. There's also a "hoverpack" item in late-game + some folks use fly-mods. I haven't gotten that far, so I end up using lookout towers + foundations to get things neatly arranged.
Oh, did they add snapping to a grid when building on foundations? There wasn't a snapping option when I played. At best, you could align one building to be directly adjacent to another, but that didn't help when making belts.
They made significant improvements to building in the Updates 4 and 5 iirc. Some basic bulk creation options, toggleable clipping, global grid alignment, etc. Coffeestain is doing a really good job of taking a good game and giving it the polish and QOL features that should turn it into a great game when it exits Early Access.