[...] I heard that natural graphite is a mess; that it's not really clean layers and there are kinks and bumps all over the graphite structure.
Graphite is absent from Nature. It's strictly man-made by pyrolysis of varied compounds like tar, sisal, polyacrylonitrile, gaseous hydrocarbons.
Especially coal is a hydrocarbon, with some more elements. It's carbon-rich, but a hydrocarbon - this allows to light it, while graphite doesn't burn.
Docs about graphite differ an awful lot from an other (except when copied as usual), even for properties as basic as density. The start compound defines much the produced graphite, the process also: impregnation steps, atmosphere, pyrolysis duration. Carbon is known precisely only as diamond.
I have never read a report about a graphite single-crystal, from which some properties like density could have been measured. Since graphite sublimates first, it takes 108 bar to melt it at 4,600K ±300K (admire the precision), so I guess nobody has crystallized it.
Most materials are usually polycrystalline, but graphite is much worse: its pure and ordered form is unknown.